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First things first. Credit for this magnificent tutorial goes directly to Quazi from International Cannagraphic. I have just reproduced this thread word for word and picture for picture. I think it is just wonderfully done and didn't want to change a single letter. I spent a while last night reading it and I really gained a great understanding about some of the teks I didn't know that much detail about. The pictures really help as well for the visual learners. Enjoy!
An Overview of Cannabis Training (ScrOG, SoG, FIM, Supercrop, LST, etc.)
Now then. After the reactions that I received on my first dive into guides for training, I thought a more complete guide was necessary as it's something I've done quite a bit more reading into since then and I've also gained experience and insight into various methods. In addition, it seems the same questions are still being asked by newer growers. There are a lot of good sources of information out there on the subject. However, I felt a compilation giving a brief explanation of them, with some examples, would allow everyone to develop a common language here. In addition, it'll help those newer to the hobby, and the forums, so they can understand just what the hell people are saying.
First, I should go over the acronyms just to get them straight so that we all know we're talking about the same things here: -ScrOG - Screen Of Green -SoG - Sea Of Green -FIM - Fuck I Missed -LST - Low Stress Training -HST - High Stress Training
With that out of the way, let's go into a small explanation as to why these methods are used and what they can help you achieve with your plants. We'll start by dispelling a few of the most prevalent myths about training: 1) Training can take place during flower. 2) Training is not just to control the height of the plant. 3) Training can be done for any strain. Though some react better than others.
With those three things out of the way, let's get into some meat and potatoes.
Training can be divided into two main categories: High Stress Training - HST Low Stress Training - LST (also a common name for a method of training so be careful with this)
The two types of training are like they sound: either more or less stressful for the plant that you are training. For the purpose of this guide and according to most of the sources out there, the differentiation is simple: LST = not physically damaging the plant HST = physically damaging the plant
Notice that I did not say harming the plant because, well, it's training; none of us are out to hurt our plants.
Both of these types of training produce similar results, but they are done in different ways. Everyone who trains has their preferred method. To help you pick the method that you'd like to choose for your grow, I'll explore the pros and cons of each. We'll go into detail about the different types of training in the next parts of this guide.
High Stress Training
1. Quick 2. Easy 3. Requires no additional parts (except to cause damage) 4. Great for larger grows
1. Creating possible sites for infection 2. Can backfire if the plant reacts poorly 3. Mostly irreversible 4. Mistakes are more costly 5. Possibly slower recovery time
Low Stress Training
1. Does not stress plants as much 2. Reversible (for the most part) 3. Forgivable 4. Great for micro grows 5. Fun to do as it's more involved
1. Requires additional parts 2. Takes more time 3. Possibly less fun to do as it's more involved (just depends on you) 4. Requires more plant manhandling
Training, when executed properly, has great results that can be seen in both quality and yield for your plants. It can be the difference between 2 big colas and some popcorn to 8-10 large colas:
Training, whether it be HST or LST, is done for the same reason: to reduce the level of auxins in the tip of the plant. Cannabis is a plant that grows with a characteristic called "apical dominance." This means that, like other plants, it will do everything it can to push a single tip towards the source of light. We call the tip of a plant that grows like this the apical tip or the terminal tip. The tips of the cannabis plants are also where the biggest colas are produced due to their proximity to the source of light.
The tip of the plant is also where a particular type of auxin (plant horomone) is most prevalent. It's called indole-3-acetic-acid (IAA). Unfortunately, due to the chemical properties of IAA, you won't see it in the rooting horomones you can buy. More than likely, you'll find indole-3-butyric-acid (IBA) and/or a-Naphthalene acetic acid (NAA); other auxins.
Now, the auxins promote growth when they are in certain levels but they can also inhibit, or stunt, the growth of certain aspects of the plants if they are at higher levels. This is the case for cannabis plants. The plant is perfectly happy pushing one bud up as far as it can to the source of light. The other buds, lower down the branch, will remain auxiliary buds and branching is not as likely to occur in these places. This is especially true in smaller, indoor environments. This is because the auxin production within the apical tip is very high, preventing the lower buds from growing out.
A very obvious example of this is in nature with the pine trees:
So, training, whether HST or LST, is done to accomplish one of two things: 1) Removing/inhibiting the main source of auxins 2) Making the plant think the apical tip is no longer the best source of light
By removing the main source of auxins, the lower (auxiliary) buds are no longer inhbited. The plant will now concentrate on the auxiliary buds and cause branching to occur in order to get itself a new apical tip. In ideal environments, the plant will grow somewhat symmetrically so that means you can very often more than double the number of growing tips.
By making the plant think it's apical tip is no longer the best source of light, it will send the message (via auxins and other chemicals) to the auxiliary buds lower down the stem that they need to grow up to get to the light. The tip is not removed, but new bud sites are formed further down the stem. Depending on the length of the stem and strain of the plant, you can sometimes get many, many bud-sites to grow this way.
In either case, you end up with more bud-sites closer to your light source than before and, most of the time, you'll end up with a more even, bushier canopy to ensure your lights are being utilized to their fullest.
Now that you've got an understanding of training, we can start to look at some examples.
Super-cropping, topping, chopping, decapitating, crushing the herd, bending the stem, FIM, call it what you will: it's high stress training (HST). Any time you are physically damaging the plant to train it, you are causing it to undergo a series of chemical and horomonal changes that will result in what everyone is looking for: more budsites on your plant.
There are 2 main types of high stress training: 1) Topping (via FIM or other method) 2) Stem mutilation
We'll start with topping. Topping involves removing the apical tip from the plant. This causes the plant undergoe a series of changes, resulting in the auxilary buds sprouting new apical tips. As discussed in part I, this is because there is no auxin generator above the tips inhibiting the growth of the sites. This will usually result in at least two bud-sites where there was one.
Another type of topping is called the FIM method. FIM stands for "Fuck I Missed." This is because, instead of completely removing the apical tip, you are only removing half of it, looking like you "missed" the top. This can results in 3, 4 or even more tops from the location. A common FIM technique, is to bend a box-razor blade so there is a curve in it. This way, you can scoop out the area necessary to make the FIM cut.
DierWolf, from the grasscity.com forums, produced an excellent image that illustrates the difference between regular topping, and the FIM technique:
So, you might be asking yourself: "if the FIM technique produces more bud sites than regular topping, why would anyone top their plants?"
Now would be a good time to look at the pros and cons of FIM vs Topping.
1. Potential to produce many bud-sites 2. More careful methods 3. Can keep canopy level the same 4. Great for small grows
1. Large risk of failure - if you cut wrong, you won't get the results you're looking for 2. Larger risk of infection - more exposed foliage 3. More time consuming 4. More difficult
1. Quick 2. Easy 3. Does not require tools 4. Great for large grows
1. Less budsite potential than the FIM technique 2. Longer recovery time
FIM is generally known to cause more bud-sites than regular topping but it is definitely more time-intensive. Topping can be as simple as using your fingernails to pop the top off of your plants as you walk along your grow. To properly FIM, precision and a tool must be used for maximum results.
Speaking of fingernails, let's look at the other type of high stress training: stem mutilation. Now, there are interesting theories, methods and discussions invovling both the science and application of this type of training. This type of training is known by many different names:
-Crushing the herd -Supercropping -Stem-smashing -Leaning the stem over
All of them have the same general idea: mutilate the stem evenly around an area so that the stem bends over at a 90 degree angle. In this case, we aren't removing a piece of the plant, but rather damaging an area of the plant so that the angle of the branch changes.
The most common methodology for crushing the stem is to pinch the stem enough that it breaks and separates a bit. Then, turn your pinch by 90 degrees and pinch again. This will cause the tip of the plant to fall over at an angle.
Supercropping can be done during vegetative growth to achieve effects similar to LST. That is: the apical tip will be bent downwards once the branch has been pinched. This causes the plant to think that it needs to send new tips to grow towards the light source.
Supercropping can also be done during flower to keep those stretchy plants from burning themselves. There are plenty of examples of supercropping well into flower w/out having too adverse of an effect on the plant: pic
Obviously, some strains will respond better than others. In addition, if you supercrop well into flower and you have some heavy budsites, you may find the stem has troubles supporting itself. Be smart about it and don't crush the stems too hard if you don't think the plant will grow out of it.
Let's check the pros and cons of this type of training: -Pros
1. Not as stressful as removing plant parts 2. Less worry of failure 3. Not as prone to infection 4. Quick and easy
1. Somewhat inprecise 2. Can have a learning curve 3. Changes for different strains
In the last type of training, I started to talk about how supercropping can be used to trick the plant by damaging the stem and causing the tip to fall to, or below, a horizontal level. This leads us into the basics for the next type of training.
It is easy to get confused about low stress training when you are first exploring cannabis training. This is because the acronym for low stress training (LST) also happens to be the name coined for a particular type of low stress training. No one is quite sure of the source, but many attribute it back to Delta or myMUSICveins (thanks greenisgold) for popularizing the name and the technique.
There are two main types of low stress training: 1) The tie-down method 2) Screen of Green (ScrOG)
Low stress training does not require any mutilation or damage to the plant which, for some, is the sole reason to use it above high stress training methods. Low stress training is done by tricking the plant into thinking the apical tips are no longer able to be the apical tips. In nature, if a branch gets blocked by another branch, or a large leaf from another tree, the plant will do it's best to navigate the growing tip so that it can continue growing upwards.
If, however, the plant cannot easily find a way to make that growing tip go back towards the light, the level of auxins will shift, and the lower sites will be called upon to try and stretch up to become the next apical tip.
This process can be repeated over, and over again in our controlled, indoor environments: apical tip grows up, apical tip trained down, other tips grow up, other tips tied down, more tips up, and so on.
Now, let's look at the two approaches to low stress training.
First we'll explore the tie-down method that is also just known as LST. There are a couple different approaches to LST. a) Constantly training a single apical tip b) Training every apical tip
The first approach involves constantly training, and untraining, the main apical tip so as to utilize as much of the growing pot as possible. TillthedayiDIE420 from rollitup has a great image detailing this method:
In the image, the 1st large number represents the week. The second large number represents the size of the pot in inches. Although it does not need to be followed exactly, the idea is there.
The second approach to LST is simple: train every apical tip down until you are happy with the bush you have.
There are many different ways to attach the training to the pot and the plant. In addition, there are many materials that you can use to apply the training.
I prefer using clipped pieces of shielded copper wiring. This reduces the amount of time you have to fuss with knots and the pieces are easily reusable.
For attaching, you can attach the tip to the base of the stem to begin with. From there, you can either put holes in your containers, or tie some rubberbands around the outside and pull the training medium down to them. They just snap in place. Very handy and easy, though the rubberbands have to be replaced:
Now that we've gone over LST, we can look at the Screen Of Green method.
The ScrOG method is almost identical to the LST method. Instead of using string or wire, a screen is fastened to the pot, buried along the edges of the pot and stretched up across the plant, or built separately from the plant. Once the plant has reached suitable height, training can begin. Once the screen is above the plant and the apical tip is long enough, it is bent down and pushed beneath the screen. This will cause the tip to grow horizontally. In addition, it will promote new tips further down the stem. These tips can then be trained downwards for horizontal growth, or trained to grow upwards in the hole of your choosing after some horizontal growth.
Eventually, the main tip will find it's way to a hole in the screen and start to grow up again. Depending on the size of your screen, you can push it back down and under to promote more growth further down the stem, or allow it to continue upwards with the new tips that you have created.
ScrOGs can be done for single plants, 2-3 plants or multiple plants in a SoG-style setup.
Once you have a nice screen of tips, or a jungle of trainings from string/wiring, you can send the plant into flower and watch the magic happen.
Now that we've looked at the different types of LST, let's look at the pros and cons of each.
LST (Tie-down method) -Pros
1. Requires very little materials 2. Can be moved from pot to pot relatively easily 3. Easy
1. Time consuming (especially if using string) 2. Materials may be harder to reuse 3. Harder for larger applications
Screen Of Green (ScrOG) -Pros
1. Easy to train once setup 2. Screens can be easily reused 3. Can be done for large applications w/out requiring much time 4. Cool as hell to look at 5. Easy to harvest
1. Requires setup 2. Hard to transport or move from pot to pot 3. Requires a bit more learning 4. Requires planning ahead of time for best results
Since both methods are so similar, it really ends up coming down to a matter of style and preference more than anything. Both produce excellent results and can greatly increase your harvest. This is especially true for micro-growers where every bud-site counts.
Speaking of every bud-site counting, we're going to explore the last bit of "training" for this guide. I put quotations because, well, it's not really a type of "training" at all. Follow along and you'll see what I'm talking about.
The Sea of Green (SoG) is not really a training method, persay. However, because the acronym often gets lumped within micro-growing styles, I felt it was worth exploring in this guide.
The Sea of Green method does not involve training the plants or changing levels of auxins like what we've talked about before. Instead, SoG allows a grower to maximize a variety of cannabis while at the same time trying to dial in a strain/method that allows for the most grams per watt.
The SoG method involves growing many plants in smaller pots. Usually this is done with clones. There are quite a few different growers who utilize the SoG method in these forums. SoG can be done on smaller scales in containers such as cut 20oz soda bottles, or it can be done by utilizing taller, 1/2-3 gallon containers, with less width. By allowing for more plants under the light, one can grow many different strains without worrying about the canopies interfering with each other as much.
The idea behind smaller SoG grows is to get bud from the soil to the tip of the plant. This is a strain-dependent characteristic, but is often a desired one from SoG growers.
Let's take a look at the pros and cons of this method.
1. Easier to grow more strains 2. Clone friendly 3. Can potentially mean increased yield
1. Higher plant count 2. Not good for all strains 3. More time-consuming
SoG is great for some who want variety and a bunch of colas sitting in their flowering chamber. However, the small size and number of plants is just too troublesome for some. Now that we've looked at the main types of training, you can make your own decision and go out there and start maximizing your yield.
I hope this has allowed you to make a decision as to the type of training you want to do. From here, there are many resources available for detailed information and pictorial examples for the type of training you decide upon.
Mostly, I just hope this guide lets you put more buds under the lights:
Kodiak created the following tutorial. It's also very good. Check out the original thread at IC Mag here.
A complete guide to topping, training and pruning
I got some requests for pointers on how to train your plants for a maximized crop, so I put this guide together. I will cover the basic idea behind topping the plant and how to apply the various techniques in combination for the best results. Keep in mind that this is only one method of growing and that there are many other ways to do it.
Topping the plant means that you remove the main shoot located on the stem. By doing so you will encourage the plant to grow into a bush with a lot of shoots, instead of one big main shoot that you get on the untopped “christmas tree”.
The reason why the plant behaves this way is because the center of growth control, the auxin transport system, is located in the main shoot apex. Sensory pigments in the leafs inform the plant of various things like how much light a leaf at a certain location gets and so on, which then enables the plant to transport energy and growth hormones to various areas.
The mechanism behind the auxin transport system is quite complex, involving various messenger molecules, growth hormones and specific proteins that trigger everything from vegetative growth to flowering in the plant. Some aspects of this mechanism are still unknown and under scientific research. What is known however is that the centre of control for this mechanism is located in the main shoot apex and that it also relies on information from the sensory pigments located in the leafs.
By removing the main shoot, the communication between the leafs and main shoot ends and the result is that the plant assigns the next shoots in line to the job. This means that the smaller shoots on the node beneath the cut starts growing faster and gain height. These shoots usually grow very slowly when the plant is left untopped. It is probably best to top the plant at night as then most of the hormones have been sent to the roots, which means that there is a smaller chance of the plant being stunted after the main shoot has been removed.
Most of the time this transition is quite fast but some plants that respond poorly to topping might have stunted growth for a while. It is possible to top a plant many times, each time the number of main shoots will double. Give your plants some time to grow before you top them, if they are topped to early they might get stunted for a while. I do top them quite early sometimes as you can probably tell from the pictures that I have included. Go by your feeling, once the plants look strong enough you can start topping and training them.
This is a good way of training the plant if one wants to make the most out of the space available. Topping is also a good way of slowing down plants that tend to stretch a lot, as each time the plant is topped it will redirect energy to a greater number of shoots. The new shoots will never grow as large as the untopped main shoot will but they will most likely produce a larger crop.
(Credit to the original creator of this picture)
There is also a technique called FIM (Fuck I Missed) topping. By leaving a small portion of the growth on the main shoot intact, the plant will for some reason assume that four shoots, instead of two, are the main shoots and they will grow evenly in height. The success of this method is usually up to the luck of the draw but you should make the cut circular so that the remaining tissue forms a “cup”. The same result can however be achieved by topping the plant twice.
Here are some plants in various stages of training.
There is also a technique called super cropping, which involves crushing of the soft inner hurd of the stem in order to gain some control over the plant, but mainly to increase health, potency and yield. This soft inner hurd is made up of cellulose and forms a network of vascular tissue that can be divided into two groups, namely the xylem and phloem. These two are responsible for the transport of water and nutrients along the stem.
Breaking the plant's inner walls will cause it to rebuild. The plant will rebuild the tissue stronger than before and this is why this technique can increase the harvest. While rebuilding the tissue the plant expands on the network of cellulose, which is why the stem grows thicker than before at the point where it was crushed. Think of it this way; instead of having a two way street for water and nutrient transport, you now have a multi-laned super highway.
If you pinch the main stem it will grow very thick, which will benefit the entire plant. Pinching the side branches will allow you to have more control over how she takes shape. Thanks to the bend on the newly crushed branch you can now redirect it in any way that you see fit. This will also allow more light to reach the lower buds. Since the branch will grow stronger at the breaking point, it will also be able to support more weight. The branches that are closest to the breaking point will also grow stronger in order to compensate for the injury.
Here we can see how the stem has grown stronger where the vascular tissue was damaged and then repaired.
The idea here is to some gain control over the shape of the plant while improving on health and increasing her yield. Pinched plants usually grow into very healthy bushes with thick stems. Super cropping is also a good way of getting several main colas. The pinched branches will eventually grow so thick that the plant will treat them as if they were main colas instead of secondary branches. The added stress that comes with super cropping might also increase potency.
Super cropping should be carried out during the second or third week of vegetative growth. Take a branch between your forefinger and thumb and proceed to pinch and twist at the same time until you feel the insides start to collapse under the pressure of your fingers. Slowly squeeze and bend the stem without snapping it. Just squeeze lightly until you feel the branch give, then let go. The branch might droop for a while but that's ok as it will heal over time.
Keep in mind that sometimes you will have to keep the plant in a vegetative state a bit longer than usual as it takes the plant some time to repair the broken tissue and redirect energy. It is probably best to choose either topping/LST training or super cropping, as both techniques have the same purpose and applying all of them at the same time might put the plant under too much stress. Pruning super cropped plants might however become necessary at some point or the other in order to ensure that the plant is functioning at it's full potential
If this technique is applied correctly and with patience, the outcome will most likely be a stronger, bushier plant and a greater harvest.
Low Stress Training
Topping the plant or Super Cropping can be considered High Stress Training (HST), which might upset the plant to some degree. There is however another option called LST or Low Stress Training.
Topping and LST training work quite well together but it's not necessary to top the plant in order to start the LST training. Some people prefer to leave the plant untopped and tie down the main shoot at ground level instead. This will have the same effect as topping it because once again, the auxin transport system located in the main shoot will dictate how the plant grows. When the main shoot is tied down, all shoots above it will grow more rapidly as the plant now assumes that these are the main shoots.
Training the plant in this way is called Low Stress Training or LST. As long as the main shoot is kept lower than the surrounding branches, they will grow rapidly in height.
These diagrams, originally posted by big_buddha, give a good picture of what I am talking about. These are excellent diagrams so many thanks to the creator.
It is possible to keep tying down each new branch as it grows, which will result in a plant that grows into a dense bush. LST training combined with topping can be a very effective way of creating a plant that makes use of all the available space. The trick here is to top the plant at each new node and to keep the internodes as short as possible. Training the plant in this manner takes some time and there is no way to reach good results by being in a hurry. As you can see, the plant in this picture has been both topped and trained. If you look closely you can see where the branches have been tied to the pot.
There are many ways to train a plant, each plant requires a slightly different treatment. The goal is however to get a plant that looks like the one in the picture above. Once that plant goes into flowering it will have many branches with many nodes, you can probably see what I mean. Once the bush gains size and starts to stretch, you will have to start pruning it carefully and wisely.
Just to demonstrate how differently plants can be trained, here are some pictures of plants in early training. All of them were topped first. By training a plant you can also slow down the stretch, especially in tropical sativas.
This Oldtimer’s Haze was stretching a lot and had quite long internodes so I topped it and trained it to grow around itself and eventually it grew into a sphere.
This Kali Mist plant did not like to be topped so I tried to slow it down by tying down the branches horizontally. In the end this plant preferred a few main colas so I stopped the training shortly after. Some plants will resist any attempts of training and respond poorly when you try. These plants will probably yield more when left untopped.
Here is an example of a Ingemar’s Punch plant that went through some serious LST training. This plant resembles a creeper vine more than a bush. Here the goal was to keep the plant as low as possible but usually the plant is allowed to grow in size and height so that it produces a larger crop. This example however illustrates the possibilities when it comes to training. Remember that even if your grow room is limited in height, you are not restricted to growing solely lowryders or other strains that stay low, as any plant can be trained to grow in any manner or form. This opens up possibilities for stealthy cab and pc grows. All you have to to is reserve some time for the training during veg and perhaps you will have to continue the training during flowering as well, like in the example above. Anything is possible.
Topping and training is also a good way to keep mother plants from growing too large. There are several good threads on how to keep bonsai moms on this forum so I will not venture further into that topic.
Scrogging, or Screen of Green means that you suspend a net over the plants and allow them to grow through it. This makes it easier to separate the growing branches so that they cover the entire area of the grow room. The scrog net also provides support as the buds can often become so heavy that that the branches cannot support them any more and break under the weight. Thereby the scrog net also removes the need for noisy fans, used to make the stems stronger through the waving effect. Personally never use fans due to limited space.
I usually train the plants for up to three months before flipping the switch, which means that they are thick stemmed and quite large in size. Although plants can be kept very low with training, my aim is to grow large and busy plants that produce the maximum amount of buds. Due to the long vegetative period, the plants are strong and healthy with an abundance of bud sites.
I try to keep the canopy even by topping the plants that stretch more but sometimes it is impossible, especially when growing both indicas and sativas at the same time. One has to adjust according to the plants and direct longer branches to the corners of the grow room, sometimes the only option is to tie the branches horizontally so that they are resting on the scrog net. This can be a strange sight as the buds keep growing vertically out of the side of the flower.
The basic idea is that the training should be complete by the time the plants start flowering and grow through the net. Sometimes a second scrog net is necessary higher up if the plants need further support.
There are also different methods when it comes to scrogging, some people tilt the net so that one side is higher than the other, as this provides a greater surface area for the buds.
Sea of Green
Sea of green or SOG is the method of growing where a multitude of smaller plants are grown instead of few larger ones. These smaller plants will mature faster and in less time than larger plants and one crop can be started while another is maturing. This saves the grower a lot of time and money as less time is required between crops. This method is also good for those wanting to make the most out of their smaller grow area.
Twice as many plants grown half as big will fill the grow space twice as fast, so harvests take place almost twice as often.
Although SOG is more of a style of growing than an actual technique that can be applied in order to increase the harvest, I still wanted to mention it here as this method of growing will under the right conditions actually increase the harvest. As opposed to growing a few larger plants in the same area that is. Since you want the buds to cover as much of the grow area as possible, one plant per sq. ft. is a good rule of thumb for SOG.
Plants should naturally not be topped when using the this method as the idea is to harvest the main cola from a whole bunch of smaller plants and topping them defeats that purpose. The SOG plants do not require any training either as that will only slow them down and delay the harvest. It is probably better to just grow more plants instead and fill out the entire surface area with as many plants as possible. In case the smaller plants do not fill up the entire area of the grow room, some minor LST training might be needed in order for them to branch out a bit more.
The SOG plants can also be Scrogged for further control over the plants. In order for this method to be truly effective, all the new plants would have to be clones from the same mother. That means that all the little plants will grow at the same speed, which is important for keeping an even canopy.
Although no topping and training is needed when growing SOG, the trimming of branches and fan leafs, especially lower ones, becomes a must because every little bit of space counts towards the harvest. By removing excess fan leafs that would otherwise block bud sites, the SOG grower improves on his yield. Since SOG grows usually contain a great number of plants in a relatively small area, the need for trimming fan leafs becomes apparent. After all, what we are after is a bountiful harvest and different methods apply to different styles of growing.
When the plant is left to grow as it chooses, it usually has more branches than it has the energy to support. This means that a lot of energy is wasted on smaller branches, especially the lower ones. The energy need is so spread out that in extreme cases flowering takes a very long time as the plant tries to supply energy evenly to every location. By removing some of the less important and weaker branches, you can ensure that the larger branches produce a greater amount of high quality bud. The bud on the lower branches that receive less light usually end up as single “pop corn” buds that never truly mature, so it is best to remove them at an early stage.
You become the “investment planner” for you plants. Observe the growth and remove any branch that has long internodes (the space between the nodes) and any branch that stays significantly lower than the main shoots. These branches will get very little light and they will also have a hard time to find they way up to the well lit area. Most of the time I end up removing almost all the growth underneath the scrog net, I only leave the fan leafs intact until the plant drops them by itself after the energy has been recovered.
When it comes to removing leaf material opinions vary, some remove leafs and others, like myself, chose not to. I have tried both methods and can honestly say that there is no positive effect really from removing leafs. Keep in mind that fan leafs are the primary location for photosynthesis and that the plant also stores surplus energy in them. By removing the leafs you do double harm, you handicap the plants ability to produce vital energy and you also remove the energy that has already been stored for future use. Furthermore, although it cannot be observed with the naked eye, light actually passes through the leafs and that is why some of the lower leafs stay green throughout the entire grow. It is better to tuck or tie the leafs under the canopy so that light reaches more bud sites, or alternatively cut the leafs in half.
Since most of the photosynthetic activity takes place in the fan leafs, the buds themselves do not need light, in other words, bud sites are activated by light when it hits the node but the energy is produced and transported to the buds from the leafs. This is where a scrog net also comes in handy, you can tie down the leafs without removing them and thereby allow more light to reach the buds while no energy is lost. The rules of pruning are a bit different when it comes to growing SOG as you might have to remove some of the fan leafs because the plants are packed so close together.
All grow rooms are different and so is each strain of cannabis. In fact every plant is different from the next so you will have to try out what works best for you. I hope that this guide at least gave you a picture of what the methods are and how they can be used for an increased harvest.
Each time a growing tip is clipped, the stem branches into two shoots, which begin to grow from the nearest leaf axils.
Pruning a growing marijuana plant is an easy way of controlling uneven growth without seriously harming the plant.
Don't prune the growing tip of a young seedling until after the first five-bladed leaves have formed, and the vegetative stage has begun.
Many growers prune the growing tips after four to five weeks growth to develop lower branches which will quickly fill all the horizontal space.
The greatest potency of the growing plant is found in the growing tips, and by three months, they should make a high quality smoke.
You can basically prune growing tips at any stage of the plant's development, but just don't overdo it.
Severe pruning can harm the growth of the plant.
It is always better to plan a pruning strategy for your developing plants, rather than haphazardly clipping off growing tips on an irregular basis.
Each time a growing tip is removed, the plant takes a few days to recover before new growth resumes on that branch.
The amount of new growth formed with continued pruning is limited by the genetic structure of the seed, and the conditions of the environment.
It is better to prune your plants at an early stage of their development, than towards the end of the vegetative stage or during flowering.
It is always better to prune growing tips in the morning than in the evening, as it gives the plant a full day to recover and heal the wounds.
It is not recommended that you prune every new node in a developing plant. Rather prune every second or third node to allow the plant time to recover.
Wait for the new node to start growing before clipping the young branch a few millimeters above the previous node's newly formed leaves.
It is always better to use a small scissors to prune your plants, than to simply pluck off the growing tips by hand.
Do not prune any growing tips if you notice that your plant's health is declining and it has started losing leaves. Although you should always smoke the pruned growing tips, plants should be pruned to develop their growth rather than for smoking purposes.
While it may be tempting to prune female buds during early flowering, your harvest will be severely reduced by doing so.
Cannabis Indica is a genetically smaller and more bushy plant than Cannabis Sativa and usually requires less pruning.
Never prune more than the single growing tip, or upper-most node, from any branch on the growing plant.
The upper-most growing tip of an unpruned marijuana plant will always be more potent that the top buds of a pruned plant grown in similar conditions.
Pruning the tallest branches ensures that the lower branches grow upwards, forming a larger surface area for the light to cover.
The clear fluid that often flows from the end of a newly pruned branch, contains substances which seal the wound and aid the healing process.
Although it is recommended that you remove all dying leaves from the plant, you should resist the temptation to prune too many healthy leaves.
To grow seedless marijuana, you should remove all the male plants as soon as they are discovered, by pruning the main stem right above the ground.
Although it may be better developed, a pruned marijuana plant does not always produce more buds than an unpruned plant.
Another good reason for pruning is to take cuttings from a strong growing, favourite plant for further hydroponic development.
Marijuana growers often prune their plants in an attempt to limit their height and prevent unwanted detection.
An alternative to pruning for developing growth, is to bend the tops of the branches over and tie the growing tips down with string or wire.
Remember that by pruning a growing tip, you are removing the most potent part of the plant, thereby spoiling it's chance of reaching full maturity.
By pruning all the buds at harvest time, rather than cutting the stem off above the ground, you could easily harvest your plant a second time.
By severely pruning your marijuana plants you are lowering their resistance to harmful natural enemies such as insects, fungus and frost.
You can make a great cup of tea, by chopping up some pruned growing tips and soaking them in boiled water for a few minutes.
Cannabis is a very hardy and adaptable plant, and will endure serious harm to it's leaves, branches and stem before it dies.
Here are some additional links regarding how to grow Cannabis.
Here is the SCROG Bible posted here by Dr. Penguin.
Dr. Penguin said: I take no credit for this article. It was reproduced with the consent of the original author.
Quote: This article is intended to provide information for new growers using the ``ScrOG'' or ``Screen of Green'' method in mini or micro cabinets under small HPS lights, in the range of 70 to 250 watts. I won't spend too much time on 400, 600 and 1000 watt grows, as that's outside the scope of my experience. See the ``links'' post below for further materials regarding 400 watt and other scrogs.
Small HPS lights, alternatives
Small HPS lights are perfect for growing cannabis in restricted space conditions, as they produce the most light from a given amount of electricity of any suitable lamp for cultivation, and produce a spectrum that is favorable for flower growth. The spectrum is not the best for vegetative growth, but that isn't really important to scrog growing, as the vegetative period is so short. Lights as small as 35 watts are available by stripping components from security lights commonly available at discount hardware stores. 250 watt lights can produce as much per foot in scrog conditions as 1000 watt lights in room growing. A single 70 watt light can produce enough for an average pot smoker in a space as small as 1 sq. ft.
MH lights are available in small sizes, but they produce less light and more heat than their HPS counterparts, and heat is an important consideration in cabinet-style growing. Some growers like the MH spectrum for vegetative growth, but there is no real vegetative period in most scrog growing. Some believe the MH spectrum produces tighter buds. I tried a 250 MH and found it to be very hot and much weaker than the HPS. In fact, the 220 HPS conversion bulb has performed better than the MH with the same ballast.
I should note that oldtimer1 states that some MH spectrum should be included in the flowering phase in order to fully develop the complexities of the psychoactive profile of a suitable plant. Perhaps a supplemental small MH could be included at the empty end of a 150-250 HPS hood.
Regarding fluorescents, the light to heat ratio is even worse than an MH, and I am not aware of any situation in micro and mini growing where I would favor them over small HPS lights (see second part for a discussion of small-scale fluorescent scrogs). Compact fluorescents have been quite popular on the boards recently, and they look quite bright to the eye, even the 20 watters. But the plants aren't fooled, and the dull yellow glow of the small HPS lamps is manna to cannabis.
Note that these lights are quite weak compared to 400, 600 or 1000 watt lights used in production growing. Intensity means that the light can be farther away from the plant and still be bright enough at the bud surface to produce. Intensity is necessary for tight bud formation.
To get the most out of a small HPS light, you must keep the bud sites within the productive range of the bulb, a lopsided sphere extending out from the lamp source. For a 250 watt light, that circle of light extends out about 20" from the lamp. For a 70 watt light, the maximum distance is apparently around 8". A group of tall, skinny plants under such a light would only be properly lit at the very tops of the plants, leaving the bottom parts shaded out and in a low intensity light field, producing small, lightweight buds at best.
Ideally you would like all the buds within that magic circle of light intensity, and you would like that sphere of light completely filled with buds. How can that be accomplished?
The scrog method
The essential detail of the scrog method is a screen, usually poultry netting, typically suspended between the planting medium and the lamp. The plants grow up to the screen and then are ``trained'' under the screen, resulting in a flat table of plant growth, a field rather than a forest. Because all the buds are growing at the same height, it is possible to get all the growth within the effective circle of light from the lamp, maximizing production from the space. It's really that simple.
Well, nothing new under the sun, the method has been used for years. In modern terms, the method was first popularized on the internet by the work of pH on the usenet group Alt Drugs Pot Cultivation, or ``ADPC'' for short. You can access ADPC from several web-based sources, and pH still posts there regularly. But the method as initially used by pH was designed to tweak production from a large area under fluorescent lights, like the ``multi-shelf'' method explained in his article on N.P. Kaye's Lycaeum site. N.P. Kaye is in fact credited with the term ``screen of green'', which pH shortened to ``ScrOG''.
I am aware of a least two growers who used scrog and HID lights before that time, one based on a mention in Robert Clarke's book ``Marijuana Botany'', which was also a source for pH. But most work involving scrog and HID lights is quite recent. It is noted by pH that the first ``yield-o-rama'' post for HID scrog was in July of 1997. I became aware of the method from a medical grower in the final days of the Hemp B.C. boards, Savapalet, a posting buddy of Aeric 77.
Before discussing the method in detail, let's explore the other alternative for small HPS lights, the plantlet sea of green method.
Sea of green
The plantlet sea of green method was developed to maximize the speed of cannabis growing in limited height situations. In a typical sea of green setup of this type, clones are planted at densities as high as 9 per sq. ft. Within a short time after being established, the lights are switched to a 12 hour dark period. What happens to the planted clone?
The clone could just sit there, stretch a bit under the light regime, and flower, producing a tiny little bud with a couple of seeds. But that rarely, if ever, happens. Instead the clone takes off in a rush of growth, forming a woody main stem and branches. If the plant is suitable for sea of green growing, it will stop short of the lights and flower. Most indica dominated plants stop short enough to be grown using this method. That process is at the heart of the sea of green method, as it results in the smallest possible plant flowering in the quickest possible time.
Why does the clone act in this manner? The actual process is subject to debate. Your author suspects that the clone reads the light switch as fall, and has a mechanism that recognizes that it's too small to produce seed. So the clone goes into a furious growth mode that stops when the plant reaches a minimum height set within its genetic software, and then flowers. Others argue that the clone's response is just a variation on the normal stretching process that happens when flowering is forced in any size plant. For purposes of the discussion here, it doesn't really matter why the response occurs, just that you can rely on it.
The problem with the sea of green method under small HPS lamps is that it produces a number of small spikes under the lamp, a forest rather than a field. The plants crowd each other out and shade the lower portions, which in any event are too far from the light source. As we discussed above, tall and skinny is not productive under a small light. I grew initially using this method, based on books and magazines that I read before designing my 250 watt system, and it worked well for many years, yielding just over 1 oz. per ft. Not bad, but it can be so much better.
Note that in the mid-90's, the term ``sea of green'' started being applied to much larger plants and grows, even multiple 1000 watt installations over room-sized grow tables, with 3 foot plants spaced at one per foot. It seems the original meaning of the term, the SSSC plantlet method, has been almost forgotten.
Basic flat, fast scrog
The screen method used by pH relied on a long vegetative period for the plants to cover a large area of screen held close to a series of fluorescent tubes. The method I will describe here uses the same sort of growth process that occurs in a plantlet method sea of green plant, and is very fast. The screen should be set about 8-12" above the planting medium, if possible. There are two purposes for that gap. First, you have to get your hands underneath the screen in order to handle the plant shoots and to remove excess growth shaded out under the screen. Second, there needs to be sufficient space for the plant to branch. Branching is essential to scrog. I prefer a space of about 10" for a 250 watt light, but some growers prefer shorter gaps for smaller lights, as little as 4-6".
Note that the screen does not have to be absolutely flat, and there are good arguments for dishing the screen to match the curvature of the light field. I don't radically dish my screen, but I do tie down the middle of the screen to prevent the screen from being pushed up, which would be counter-productive.
The clones are set under the screen at a density of about 1 plant per sq. ft. Experience in using the method with various types of plants may result in more or fewer plants, but 1 per ft. is a good starting point. Note that plant density is much lower than for plantlet-method sea of green. That means fewer clones to manage and fewer plants to be holding in a bust, a factor in sentencing guidelines.
Why clones, by the way? By the time you find out which plants are male and female from seed, it would be impossible to extract the males from the foliage wound into the screen and fill in the gaps with female shoots, without a real mess on your hands. Seed plants also waste several inches of height before a mature stem section is reached from which branching can begin, whereas clones branch right from the medium. Height control is typically a limiting factor in cabinet growing. With female seeds it may be possible to grow a predictable scrog by raising the screen height, making up for the wasted stem length. Seed plants may react differently to forcing as well. I have no experience in scrog from seed.
The clones are established and kicked into vegetative growth. Assuming an 8-12" gap, just about the time where the growing tips penetrate a few inches above the screen, say at two weeks, the lights are switched to a 12 hour dark period. Ideally a response similar to the sea of green method kicks in as explained above. Instead of stopping and flowering, the plants take off, filling the screen with growth. At a density of 1 plant per ft., it usually works out that the plants stop and ``crown off'' just as the screen is filled. It's really magic to see it happen. Note that this timing method is not universal. Different plants may require more vegetative growth, or perhaps even less. My advice is to start by forcing early, because overgrowth creates an unproductive canopy, more salad than buds.
The timing is so critical. You must be around during this period to guide the growth under the screen, and to make sure all gaps in the screen are filled, one bud site per screen hole with standard poultry netting (2 x 3 inch holes). I have no position on removing fan leaves in general, but in a small scrog grow, fan leaves would overwhelm the neighboring buds, and normally they are removed. Get a good sharp, clean set of pruning scissors and just leave them with the grow. You'll need them every couple of days during this period. Note that some growers disagree, so feel free to experiment. I'm no expert on the matter, but I haul out tubs of leaves and get pretty decent results, I think.
Training really isn't difficult. With a limber plant I usually let the shoots grow vertically above the screen and then pull them under by the stem, re-orienting the stem horizontally under the screen to line up bud sites with screen holes. You don't have to tie anything down, as the upward pressure of the stem will nail the foliage to the screen, but some growers like to tie off stems to the screen during the early phases of screen filling. Here's what one grower, Ultimate, has to say on the subject:
``I swear by twist ties and have a huge stock. They can be found just about anywhere. Purchase ties which are most flexible (wire with the smallest diameter) and coated with plastic not paper, as the paper will eventually mold.
``So why twist tie? Two reasons when training for in any screen application.
1. Pre-training. (Exact placement of main stems, growth shoots and branches)
2. Bud-training. (Bending, stem crushing/crimping, and repositioning)
``When initially induced to 12/12, the main tip/tips that hit the netting are immediately trained 90 degrees perpendicular to the netting. This allows for the light to concentrate the most productive part of the plant, forcing the most efficient production the plant can dish out. Branches under the netting are allowed some time to reach the light, but less than half will see light because you're concentrating on efficiency. The most efficient growth will occur where the main stem bends on a 90 degree and beyond, which receives the most light.
``I like to leave the ties long enough for the plant hold the shape desired. Main stem usually around the second week (give or take) , and branches will always vary. Branches coming off the main stem parallel to the netting are spread as far from the main stem as possible making for a even canopy, more bud sites per square, and controlling overall height.
``To a certain extent the buds freeze at a certain point and height/stem length slows. The canopy height is close to being established, but some plants are more vigorous than others and continue stretch beyond the rest of the crop. When bud training the longer colas are controlled by bending and tying down to the screen with twist ties. In extreme cases crushing/crimping is necessary. Moldy buds can be avoided by repositioning buds growing against each other. By using twist ties each bud can be positioned where air flows between each cola allowing efficient light dispersal within the canopy and better air flow.
``Without ties? Yield was lower. A few larger colas had to be tied down shielding smaller buds from direct light, not to mention forcing the light to be raised higher, lowering production (This can be resolved by switching to a more intense bulb) . Some branches grew buds with LONG stems between the screen and base of the cola to compete with the large colas. Hybrid vigor in some cases, or plants which tend to "stretch" more than others eventually straighten out the 90 degree angle exposing less area of the most efficient portion on the plant and eventually stretches to a point where more stem was exposed to direct light, above the screen than desired. A view from the bottom (planter to the screen) showed that efficiency could be improved.''
Some plants have brittle stems, and are difficult to train. It is possible to bend a stem by crushing it lightly at the bend. So long as the structures in the plant that carry fluids aren't damaged too much, the shoot will heal and be just fine (thanks to Uncle Ben for that trick). It may also be possible to top brittle plants under the screen, so that the future growth will be in several, more slender shoots. I have no experience in training a scrog grow by topping.
After the screen is filled all growth under the screen must be clipped off. Shaded growth quickly shrivels and dies, leaving ideal growth mediums for mold. Excess leaves and shoots should be clipped close to the stem, to avoid leaving stumps as mold sites. Robert Clarke recommends pruning away from the stem, but a lot of the standard advice has to be discarded when dealing with the special conditions of a scrog grow. The space under the screen is dark and humid, and you want as little plant material under there as possible. You will haul out buckets of leaves and excess shoots from a scrog grow, but the plants can take it. Clip away.
Subsequent pruning is really limited once the plant sets buds and stops growing. Some plants develop large leaves from the buds themselves, and if the leaves shade out neighboring bud sites, I find they must be removed. But that's about it. Most of the flowering time in a scrog grow the maintenance level is near zero.
If everything goes well, the extra time required for the plants to reach the screen before the flowering period is lengthened by only about two weeks. No additional time is required to fill the screen, because that time is the same used by the sea of green method to add height. The plants end up just as long, but the growth is directed horizontally. Typically a flat scrog grow ends up resembling a tropical forest canopy, with all the buds in a thick carpet extending 8-10" above the screen. The area underneath the screen contains the tree trunks that support the canopy, like piping connecting the root mat to the canopy.
Does it matter how the canopy is created? Not particularly, in my experience. There does not seem to be a lot of difference between buds that would come from sites lower on side branches from those at the actual tip of the plant. For the most part, a bud is a bud in this method. Note that the buds grown in a scrog field are each a piece of what would be a vertical cola. Each bud grows up vertically 90 degrees from the stem. You are familiar with how a cola is made up of individual bunches of flowers connected to the stem in an overlapping spiral, producing a structure that looks like a single unit. In scrog, each one of those florets matures into a small bud in their own right, typically 4-8" tall, about the size of a cigar. They aren't donkey dicks, and you won't impress the editors of High Times into featuring your buds in the centerfold, but weight is all we're interested in, not appearance. As I say, it all looks the same in the bong bowl.
How much weight? I have shown that it is possible to reach over 2 oz. per ft. with a suitable plant and enough light density. 400 watt growers have reported up to 2.4 ounces per foot in a flat scrog. In a compressed grow, using shielded lights in a box of screen, I did nearly 2.6 ounces per foot, measured by canopy area. I suspect that 70-75 watts per sq. ft. is about the minimum to reach that kind of production, but I don't know for sure. Your results may vary, but certainly you will do better using scrog than small-scale sea of green at any light density. As an experienced plantlet-method sea of green grower, I feel comfortable stating that as a fact.
Anyone can reach the benchmark production numbers, but you must concentrate on filling the screen quickly and completely. If loose and tall would yield better, then scrog wouldn't work in the first place. You want the canopy to be low and tight, except on the edges, and one bud per hole. Screen fill density is all important to making weight.
A side note regarding the measurement and reporting of production is appropriate here. For the most part, growers on the boards talk in terms of so many ounces per square foot of growing area, apologies to the metric system. Some growers feel it is more appropriate to measure production in terms of HPS watts, taking into account how efficiently the grower uses the lamp, and our host, ~shabang~ has proposed a ``garden efficiency'' measurement, or ``GE''. In cabinet growing the area under cultivation cannot be expanded, and the lamps are typically very small, especially in comparison to any kind of production grow. I believe measuring output per watt would favor underlit grows, given an equal amount of space being used. Cabinet growers want to know how to produce the greatest weight of buds in the space they have, not how to conserve lamp power. Indeed, a cabinet grower should use the greatest amount of lamp power than can be cooled. Accordingly, I favor reporting production by area, but I encourage reporting a complete set of information about the grow so that light density can be taken into account by those so inclined. A ``yield-o-rama'' report or ``YOR'' is a good compromise. You can find information about the YOR on the usenet group ADPC in posts by Old Ketchup Lungs and other posters.
What can go wrong with a flat scrog grow? The worst thing you can do is to allow the plants to grow too long. You would think that excess growth could be cut out or moved to vertical screens, but in practice I find it's difficult to recover from a badly overgrown screen. Plants that grow into and fill the screen seem to put on better bud weight than overgrown plants that are tied down and whacked back to fit. Error on the side of forcing early, learn from what happens and adjust on the next crop.
Vegetative fills, FIM and topping
The fast, flat method relies on the flowering stretch to fill. It's the fastest, most reliable method, and the most likely to produce a short and dense canopy.
Sometimes it is not possible to use one plant per foot, particulary for grows with feminized seeds, where the grower cannot afford room to clone and hold mothers. Some growers believe vegetative fills are beneficial, but I haven't seen the weight reports to prove it.
Other growers believe that topping or FIM treatment might be beneficial in producing more branching. I think that might be true for some stiff indica's that do not branch well, but most plants will produce more than sufficient branches under the fast method at one plant per foot.
My advice is to stick with the proven method at least the first few times out. Make the benchmark weight, learn what that takes and then you can experiment. For growers who must make fewer plants cover the screen, be cautious and do not let the plant grow too long. Error on the side of short filling the screen the first time, and then adjust accordingly. An overgrown screen is difficult to recover from, particularly in the tight quarters in which a low plant density grow is likely to occur (no room, no money, usually means a micro grow).
When judging a scrog grow you see posted on this board, ignore the look of the buds and concentrate on weight. Scrog is a production method, and it's not designed to produce photogenic buds. A fair number of grows I have seen recently on the boards used the screen more to locate and support tall bud wands. You can get away with that with lights of 400 watts and over, but even then I haven't seen the kind of weight a tight, short scrog canopy can produce.
Also known as ``buddus interruptus'', the procedure is to switch the lights to 24/0 for a day or two about at the end of the fifth week of flowering, when the buds seem to stall out. It should only be done once during the crop, and for no more than two days. The best technique is to switch for one day, wait a couple of days to observe the effect, and then give it one more day if the buds haven't responded. This is not the same as ``double budding'', as the plant is never actually kicked into vegetative growth.
If the plants react well, you will see tufts of additional flowering parts standing out from the sides of the buds like little towers. Done early enough, these extra parts should finish in time, and they will add extra weight to the crop. This technique can be particularly valuable in scrog, given the large number of smaller buds.
A caveat is in order, not all plants respond well. Some don't react to the light change at all, and a very few may be disturbed into uncontrolled growth from the tops of the buds. You might be concerned with a tendency for male parts to be produced, but I've been practising this method for a long time, and I've never seen a ``hermie''.
Many people have been excited about the scrog method and have dreamt up all sorts of ways to expand production, myself included in the mad scientist crowd. The most common variation is the ``bog'' method.
Bog for ``box of green'', was first coined by Kunta and further developed by chthonic and several other growers. Added to the horizontal screen are vertical screens around the perimeter. Either additional plants are used at the edges, or the scrog field plants are grown longer, but either way, the additional foliage is allowed to grow up the outside of the vertical screen, taking advantage of wasted air space above the field. It also allows plants at the edge of the field to get into the circle of intensity from the bulb.
Imagine the light field as a circle sitting tangent to a horizontal line. Imagine your plant as a point on the line outside of the circle. How can the plant get inside the circle? By going up. You might equate this method to an ``arena'' grow in this regard. An extension on the bog theme is spiral bog, first coined by chthonic. In a spiral bog the plants are allowed to add considerable vegetation, which is trained around the box in a laid-down spiral, like this (but flatter): //////. This method allows all the screen area to be densely filled with bud sites.
There are two ways to fill the vertical bog screens, as I mentioned. The first is to use more plants, which are added to the edges of the grow. When the horizontal scrog field plants are forced to flower, the plants on the edge are allowed to grow vertically like sea of green plants, the resulting growth being trained to the vertical screens. If the growth is too tall for the screens, it can be laid down at an angle, like a spiral bog grow. The advantage of this type of bog grow is reliability and speed, since the horizontal field is filled in exactly the same manner as in a normal scrog grow. The disadvantage is that the number of plants is increased to near plantlet-method sea of green levels.
The second method is to use the same number of plants as in a standard scrog grow, or thereabouts, but to allow them to grow longer before forcing, around another week or two of growth seems to be about right. This process proved to be tricky for me at first, but once I piled up some experience in timing and training, I found the method to be superior. Several growers have been successful at 70 watts. Here's what chthonic, a pioneer in the method, had to say about his experiences with 70 watt HPS lights:
``The quickest and most successful approach that I have found to train a bog grow is to lower the horizontal screen to within 6" of the soil and grow 2 plants per sq. ft. straight up to the vertical training screens. As it's a box driven by a 70-watt bulb, the height from the horizontal screen to the roof is only 12". The plants grow unhindered 18" from the soil up through a narrow band of the horizontal screen and onto the verticals until they touch the roof. Then they are laid down horizontally and trained in a spiral fashion /// around the vertical training screens. Spiral bog or s/bog. The cabinet is small; spiral training is the only way to direct the shoots so it just happens...
``The spiral training can go one of two ways. The entire plant can be bent over in one direction and trained along with the rest of the plants in a clockwise or counter-clockwise fashion around the vertical training screens. Or the plant can be trained as it naturally branched, trained in opposite directions along the vertical training screens.''
Any method of growing should be analyzed not only for production over the space used, but also for production over time. Just for the sake of argument, let's suppose a plantlet-method sea of green method produces 1 ounce per ft., and the subject plant takes 60 days to complete its life cycle. That would be .017 oz. per ft./day. Let's suppose a scrog grow takes two weeks longer, 74 days, and produces 1 1/2 oz. That would be .020 oz. per ft/day, advantage scrog. Let's suppose than an extended bog grow takes two more weeks than a scrog grow, 88 days, and produces 2 oz. That would be .023 oz. per ft. day., advantage extended bog.
Note that it's possible to shorten the cycle by growing plants in a separate area for about two weeks and then adding them to the scrog setup. But most micro and mini growers don't have room for a separate growing area.
The ``bog'' term is subject to some debate. Chthonic believes that the term should be used for a box of foliage that surrounds a light held in a vertical position. Such a setup can be an outstanding way to get the most of out small security lights in the 70-100 range. But I think for a larger light, like a 150 or 250, it is necessary for the light to be in the normal horizontal position above the box. Personally, your author thinks that bog can be used as a general term to describe such a grow, and I don't really know what other term to use. Chthonic believes this type of grow can be referred to as an arena grow, but I've usually seen that term applied to free-standing plants rather than a box of screen. In my recent compressed grows using shielded lights, I coined the terms ``h/bog'' and ``v/bog'', stealing from chthonic's notation, but no one else has picked up on the lingo. Time will tell what terms become attached to these methods. Most people just use the generic term ``scrog''. Fair enough.
Finally, hollow screen forms do not have to be in the shape of square-cornered boxes. I've seen one grower using small HPS lights who shaped his screen into a deep bowl shape, with the light suspended in the middle. Posts on ADPC describe inverted V shapes, and cylinder forms have sprung up at Cannabis World. A single ``correct'' way to do this probably doesn't exist.
At this point, these methods are so new that every grow provides significant information. My advice to those new to the scrog method is to get a few fast, flat scrog grows under your belt first to get used to the process. But do add the vertical screens regardless, and capture whatever excess growth you can on the verticals, as there is no reason not to handle as much growth as you can.
The final extension of this concept was thought up by Kunta, and dispenses with the horizontal screen entirely. I coined the term for the method, ``v-scrog'', for vertical scrog. Vertical screens extend from the plant medium all the way up to the top of the growing space. The light is not in a reflector at the top of the space, but is suspended vertically in the middle of a tube of foliage, approaching peg's Rama concept for zero-g cannabis growing. Note that the entire light field is used, not just from the bottom half of the lamp and what comes off the reflector. The foliage area is stunning. Imagine a 2 x 2 cabinet with a v-scrog screen held 4" from the walls, with a gap in the front screen for maintenance. Suppose the buds fill up about 3' of the vertical screen. We're talking 4 screens, each 4' in area (16" x 36"). Take off a couple of inches for corner overlap and a gap in the front for access, and that's nearly 14 sq. ft. of screen in the same space that supports 4' of flat screen. Even if the production per foot were half, and it would be less due to the loss of the 3D flat scrog field, you're still talking 3 ½ ounces per foot!
Can that really be possible? Not so far. I have grown two v-scrog's that were mostly failures, but I have modified the growing space to correct the problems and I will continue testing sometime in the future. The problems so far involve the time needed to fill the screen area, which could reduce the production over time substantially, and the ability to handle the moisture load produced by the massive amount of foliage. I am also not the world's most talented trainer, but chthonic, Ultimate, Eugene and others have done very well in tiny vertical box forms with 70 watt lamps.
Even if production isn't dramatically better than horizontal methods, v-scrog is a promising solution to growing in very restricted height conditions. It might be possible to grow a productive crop with 150 and 250 watt lamps in as little as 2', maybe less. Since the light-to-foliage gap is horizontal, the only absolute vertical needs are for the plant container and a gap between the end of the downward-pointing bulb and the planting medium. Plant growth could be controlled by training it across the vertical screen, which could be any reasonable height.
Soil or hydro?
I have read nearly every scrog post on this board, and a lot of the activity on other boards and at ADPC, and it appears that a successful scrog can be done using plants in pots as well as with more exotic hydroponic systems. But there are a few elements of scrog growing that tend to favor an active hyrdroponic setup.
Once you get past a small, flat scrog grow, it becomes very difficult to train a more complex grow by reaching into the cabinet space. I would never design a sizable scrog system, or any bog-type grow, without the capability of rolling or sliding out the plant container and screens as a single unit. Obviously that means that the screen should be connected to the plant container, or possibly to a common substrate, like a plywood base. The screen does not need to be sturdy, it's just a guide, so there are many ways this could be done. But obviously it is much easier to slide out an empty container than one full of water (DWC) or soil.
Although I lack experience in using soil intensively, active hydro systems allow freshly rooted clones to have direct access to very high levels of nutrients immediately. That may mean that active hydro scrogs will evolve quicker than soil or DWC grows. I don't believe there is enough experience available to express a firm opinion on this matter, and certainly I have seen many fine DWC grows recently. For that matter, the best 400 HPS production number I've seen was accomplished in soil.
First-time growers, fluorescent lights
Scrog is not a difficult method to use, and new growers should not hesitate to try it. In fact, because most new growers are using small lights, often fluorescents, getting a reasonable harvest almost requires scrog, or a similar method such as paper-clip training or FIM (look it up). I favor scrog training over FIM because it is easier and quicker. FIM is probably a better method for larger lights, 400 and up, where the height of the bud wand can be handled.
New growers are probably going to use soil or DWC, both of which produce good results with scrog. Soil growers should avoid pots, which restrict the size of the root mat and take up precious vertical space. Instead, a plastic pan about the size and shape of the growing space should be used, which will maximize the root mat. It doesn't need to be very deep, about 6" would be suitable.
A good first choice would be a 70 HPS lamp or two in a space about 1-3 square foot, using soil or DWC. The cost of the materials needed is minimal, and the output from 70 HPS lamps is proven. You can expect to get 1-2 ounces per foot, and in presentable buds.
If fluorescents must be used, avoid compact bulbs and stick with tubes. As mentioned above, scrog as envisioned by pH was designed to be used with fluorescent tubes, stacking multiple grows in a single space to make up for the lower production. The design keeps the canopy flat and a few inches away from the surface of the bulb. Compact fluorescents tend to wrap the tube surface inside themselves, making the light from those surfaces available only by reflection. Further, by being compact they act as a point source without the required intensity to back it up.
A fluorescent tube grow could be accomplished in a space as small as 2' square, to accomodate a series of tubes, or a footlocker-type space, maybe the bottom of a closet, to take 4' tubes. It would be wise in either case to mount the ballasts outside the growing space to help with heat.
Getting the most from a fluorescent grow requires keeping the canopy tight and close to the tubes. Use one plant per foot, an 8-12" screen gap and force when the plants hit the screen, which will produce the fastest and most predictable screen fill, and will tend to keep the canopy in check. Using vegetative growth to fill the screen is an advanced technique, and I would avoid it unless you are restricted to a fewer number of plants by circumstances.
There are several myths floating around the boards about fluorescents vs. HPS lamps. It is often said that HPS lamps are expensive, but it isn't really so. Security lights containing HPS bulbs and ballasts can be purchased at discount hardware stores, and separate ballasts are available from online sources at very reasonable prices. 70 HPS security lamps go as low as $30-50. Remember also that HPS lamps have a higher mean output over time compared to their rating, and last much longer than fluoros.
It is often said that HPS lamps are hotter than fluorescents, but that too is a myth. Fluorescent lamps, aside from corporate b.s. by Lights of America, are less efficient than small HPS lamps, and therefore produce more heat per watt. To say an HPS lamp is hotter in the context of growing is to say a burning match is hotter than a radiator; it's true, but which will heat a room? A fluorescent spreads the heat over a larger area and therefore feels less hot to the hand. HPS and fluorescent tubes have an advantage in separate ballasts that can mounted outside the growing space. Compact electronic ballast fluorescents are more efficient than magnetic ballast tubes, but all of the heat they produce is confined in the growing space.
If you must use fluorescents, be realistic and don't expect to be bowled over by the buds. Depending on the plant they will either be light and feathery, or hard, but very small. You can grower larger and harder buds with fluorescents, but only by stacking up a wasteful amount of wattage on a very few bud sites. If you would like to compare some fluorescent and small HPS grows by wattage, there is a link below that will lead you to a post that compiles the best near-harvest pictures on a non-judgemental basis. People get very heated on this board pro and con regarding fluorescents (guilty), so look and make your own decision based on real grows.
Scrog growing works best with clones, but that requires a mother area which may not be possible for a new grower. Feminized seeds from Dutch Passion should work as well, though I would provide a couple more inches of screen gap to allow for the portion of the seed plant stem that will not produce branches. Branching is fundamental to scrog.
If it is not possible to produce clones or to acquire feminized seeds, then I would not use scrog. An alternate method would be to grow each seed in separate soil containers and use plantlet method sea of green, paper-clip training or FIM to control height. When the males show, they can be removed from the growing area, and the remaining females re-arranged to best suit the light source. Using a plantlet method pretty much requires an HPS lamp to get decent production, as much of the growing surface will be vertical. Fluorescent tube lamps lack intensity, as they spread their light over a large area, and compact fluorescents simply lack enough punch to act as point-source lights. Use a small HPS lamp and keep the plants trained low and flat as possible, and you should yield at least an ounce per foot.
Basic design elements
There are essentially two classes of HPS lamps when it comes to scrog growing, the small ``security light'' types, in the 50-100 range, and larger lamps in the 150-250-400 range. The best way to plan your own design is to see what others are doing. Exercise the search engine and look for scrog grows with similar-sized areas and lamps, analyze their results and plan accordingly.
The smaller lamps need to be held quite close to the canopy, as the effective range in which they will produce tight buds is limited. A 70 HPS has a range of about 8", for example. That means the distance from the screen to the light should be only an inch or two outside the range, to allow for some vertical stretch, and the distance from the lamp to the edge of the space has to be computed keeping in mind that the light is traveling on the longer diagonal out and down to the canopy. Using the standard of 50 HPS watts per square foot of canopy will produce good results, but I would shoot for more like 70-75, meaning that a 70 would be perfect for a square foot of screen. If you wished to grow with two or more 70-100 HPS lamps, the lights should be distributed over the canopy, not bunched together.
The 50-70 watts per square foot rule applies to the larger lights as well, but as power increases the limit is more negotiable. Within the confines of a scrog cabinet or box, a 400 watt lamp has a lot of power directly underneath it. Asking a 400 watt lamp to light an 8 square foot area means skirting the lower limit of the lamp power, but for the areas close to the lamp the intensity is far greater. By keeping the canopy directly under the lamp short, and by allowing the growth on the fringes to get taller, one can leverage the power of the 400 to a larger space. 400 watt lamps are therefore an excellent match with an arena, or bog type of grow. It is also possible, but not confirmed, that 400 HPS lamps could produce better with a supercropping type method, like FIM, instead of scrog. It's probably a close thing, and maybe a mixture of a horizontal scrog canopy under the lamp and FIM-type plants around the edges would be superior, a true ``arena'' grow.
The 150 and 250 watt lamps don't have that kind of power, and the canopy must be kept relatively close. The 250 has a reach of 20" within which it can tighten up buds, and therefore a 2' x 2' space is about as far as you can push the lamp and keep the production per foot up. Because the area under the lamp is relatively small, using a bog or arena type of grow becomes more difficult, as the most productive area, the horizontal field, becomes pinched down. These lamps are probably better used with a basic flat scrog, although there is no reason not to allow some growth on the vertical walls if it can be arranged within the space. Certainly, in any flat scrog grow, you have nothing to lose by letting the very outside row of buds grow tall, even to the extent of using additional plants to get that result. I see a lot of flat scrog grows where the growth thins out on the edges with bare walls surrounding the bulb. Error on the side of higher plant densities, and use the outside space to your advantage.
Note that while the smaller ``security light'' HPS lamps lack reach alone, added to a larger lamp's light field they can be useful as supplements to balance out a light field and to add some punch. For example, in a 2'x 2' cabinet, a 70 HPS added to the empty end of a 250 HPS hood would provide a combination of 80 HPS watts per foot, and would illuminate the overall space more evenly. If you are inclined to try a small MH light, perhaps you could add both light and some spectrum balance. I've also seen compact and tube fluorescents added as supplements, but that's like lighting a candle in sunlight; not much help, unless some extra heat is needed. If you're adding watts, make them count.
Height is often a restrictive element when designing a cabinet grow, particularly if mother and cloning space is needed in the same space. An unshielded (open bulb) 250 grow is perfectly suited to a space 2' x 2' x 4'. But by using a horizontal shield of tempered glass, or a plastic like lexan or plexiglass, the heat from the lamp can be confined and controlled, and up to a foot of space can be recovered by tightening up all the other elements as much as possible. Lexan or plexiglass sheets are available at discount hardware stores, can be cut with normal tools (sawed, or scored and snapped), and are modestly priced. Designing such a grow means using an extra fan to cool each compartment space, or providing for airflow from the growing area through the barrier.
Designing a cabinet in terms of the vertical space needed is best done by working backwards. Start with the known dimensions of the basic elements, the height of the plant container, the medium to screen gap and the thickness of the lamp/hood assembly. That leaves the growing space above the screen, which is somewhat negotiable. If you keep your canopy low and tight, using the flowering stretch to fill the screen in the classic fast, flat scrog fashion, none of the buds will get much bigger than 8-10" above the screen.
There has to be a gap between the top of the buds and the lamp for two reasons. First, obviously, the whole canopy must see the lamp. Second, the tops of the buds can't be fried by the lamp. Even with shielding some gap is necessary, as the tops of some varieties react badly to being in close proximity to an intense light source, producing thick stem growth that erupts from the bud tops.
Cooling and airflow are the final design element. Even with shielding there must be adequate airflow through the canopy to avoid mold, and to carry off the moisture load created by the plants. A 4' canopy under a 250 HPS will pull about a half gallon per day through the leaves, and that water has to be removed, regardless of the temperature. With the smaller HPS lamps probably ``muffin'' type axial fans are sufficient, available at many hardware stores, all growstores, and online at sites like Grainger.com, which sells Dayton and Comair fans for reasonable prices. The Comair ball-bearing axials last much longer than the solid bearing Daytons, but they are noisier; my 115 CFM 5N471 Comair's sound like a helicopter starting up.
Note that Grainger apparently checks for obvious individual accounts, so be cautious. Use a valid federal tax number (like your employer's), a business address if you can, or at least use the term ``suite'' rather than apartment, and a phone number that answers at the business name. Not everyone can accept packages at work of course, so you may not be able to access Grainger, which is a shame.
Larger setups require more fan power, say about .5 to 1 CFM per HPS watt as a decent guide, and are usually best ventilated with an industrial ``squirrel cage'' type blower, available from the same sources. Grainger has a nice selection at reasonable prices, with several different configurations to match the requirements of cabinet growing. Usually room has to be made available in the cabinet for the hardware, so look for designs that are compact and easy to mount in a given space. The Dayton 4C754 200 CFM axial is an excellent choice, $80-90 at Grainger, but using the Overgrow search engine with the word ``Dayton'' should provide a wealth of other examples. Dayton and Rubbermaid make a lot of money from pot growers; I wonder if they realize that?
Usually the fan is mounted to blow the air out, sucking it up through the canopy from an inlet into the box. It would be better in theory for the fan to blow into the confined space, to produce an over-pressure rather than a partal vacuum. But it's easier to light-proof a space with the fan power sucking the door against the seals than to be fighting air pressure.
Fans for smaller grows can simply be controlled by the light timer, always on when the lights are burning. Larger grows with squirrel cage fans need to be controlled by a line thermostat. I would avoid the cheapo hardware store models and go with something decent, like the Dayton 2E728 at Grainger for about $40-50. If you're using a shielded grow with outside air inlets, you may find humidity is the problem rather than temperature. In that case a line humidistat or a thermostat and humidistat in parallel might provide the best control.
Fresh or room air inlets should be a match with the space and the airflow. A general guide is to provide about .03-.05 square inch of inflow space per HPS watt. For example, a 3" circular plastic tube inlet would be a minimum requirement for a 250 HPS grow. Air inlets and outlets need to be arranged to avoid light leaks into the growing space. Turning the air duct 90 degrees and avoiding reflections with flat-black paint inside the duct is sufficient. For example, a ABS plastic plumbing elbow seems to be popular these days.
The prototypical scrog screen is poultry netting, which consists of 2" x 3" irregular hexagons, about 24 per foot. Poultry netting seems to space out the buds just right, in my experience. I see other growers using various types of square plastic netting, and quite a few weaving their own between sticks with wire or fishing line. If you use square holes, I would tend to size them at about 2 1/2" or a little less, but in no case would I go smaller than 2". Poultry netting costs nothing, but it does have the disadvantage of cut wire ends around the edges which always seem to be diabolically placed to slice up your hands and arms. Whatever you use, remember it doesn't have to be very sturdy. Don't steal growing space with wide wood pieces around the edges. Use something like a thin dowel, or stiff heavy-gauge wire to secure the screen.
Finally, don't neglect safety in any grow. When using electrical devices around water, a GFCI-protected outlet is a must. Before doing anything else, learn a few basics about electricity. Most of the basic grow guides do a reasonable job, but plenty of information is available online. This is suppose to be fun, but it's not a daredevil sport, so don't kill yourself doing it!
Hopefully this will give you an idea of where we stand on small level scrog methods and will answer some of the basic questions. In spite of the long history of the use of screens and netting in cannabis growing, accelerated scrog growing under HID lights is a wide open field, and each new grower can add experience and ideas to the mix.
Editorial assistance by newbie, except for the last three sections, which are all my fault. Additional input by chthonic and Ultimate as noted. Thanks to pH, Uncle Ben, Ganja Baron and Teahead for assistance and suggestions on specific topics. I should also acknowledge indirect input by Bongo and Shuzzit, as well as the other growers mentioned in the article.
Note: I have retired from internet posting activities. Anyone who cares to copy this post and continue with it is welcome, but remember it should always be open to edits from the community, rather than being one poster's opinion. - SCW
Quote: Dr. Penguin said: You can't enter it into the contest of course but I would think that as long as acknowledgement is given, reposting information should be fine...
i agree, there is credit given to the original authors, and you even have links to the original articles. awesome stuff
i'm going to sticky this as well.
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