Many of you marijuana growers have probably heard the term “ScrOG” before. Much like many growing techniques, scrogging marijuana strives to make the process a little bit easier and a lot more beneficial. The term “ScrOG” is an abbreviation of “Screen of Green.”
The idea behind the scrog method is to optimize your lights and to bring lower buds up to the top of the canopy where they could produce higher yields.
It’s a method that has been around for a while (prior to high-intensity discharge—HID—lamps) and has been used effectively, even with basic fluorescent lights.
What is scrogging?
Marijuana growers are always looking for the next best way to get their plants to grow the most efficiently. High yields, potent buds, and bushy plants make the world go ‘round for growers. One trick to getting your plants to be bushier and use up their space more efficiently is called scrogging.
The term “SCROG” in scrogging actually comes from “Screen of Green.” Scrogging is a type of training for marijuana plants that involves securing a screen above the canopy of your plants, and then tying the growth from the plants onto the screen as time goes on.
Tip: make sure to download my free Grow Bible for more advanced growing techniques
Proper scrogging works best if you also use other methods, such as topping. Topping basically involves cutting off the tops of your marijuana plants, so they grow outwards rather than upwards. This helps them grow more branches and become bushier, and scrogging helps every part of those branches and leaves to get exposed to sunlight, making for an extremely efficient use of space.
Scrogging is perfect for people who live in a state where growing marijuana is legal, but only in small amounts. For example, several states in the US let you grow five plants or less.
If you are trying to get as much weed out of your garden as possible, this isn’t very many. Scrogging lets you get the most “bang for your buck” when you have to grow in limited numbers.
Scrogging is especially useful for people who would like to grow large Sativas in a smaller space. It lets them manipulate the growth until every bit of light is hitting the plants somewhere, rather than being wasted by hitting the floor instead.
It’s important to know what your entire grow room needs before you even think about scrogging. For the grow room part, the following items are an example of what you could use:
1 x 3x3 foot tent
1 x 400 watt MH during vegetative stage
1 x 400-watt HPS during flowering stage
1 x 9,000 feet cubed extractor
1 x 10,500 feet cubed filter
1 x 3,500 feet cubed inlet
4 x 6.5-gallon pot
4 x Amnesia cuttings
Flower Power nutrients
Tip: read my article How to build a grow room for more information
In terms of equipment for the actual act of scrogging, you will simply need a screen, scissors, and some large pots. Let’s look at some of the details behind each of these.
This is the most obvious (and perhaps the most important) piece of equipment you will need for scrogging. The actual screen is not as important as how you use it, however. Keep in mind that you will just need to be able to tie the branches of your marijuana plants to it several times. It will eventually create a blanket of leaves and buds all at the exact same height.
Although any sharp scissors will do, you shouldn’t just pick up scissors from your office and start using that. Instead, make sure it is very sharp, then clean and sterilize it before using it on your plants. Much like you would be careful around a wound on a person to prevent infection, the same precautions are necessary on the “wounds” you will make on your marijuana plants.
Assuming you won’t have a large number of plants to grow (since scrogging is usually used by people who can only grow a limited number of marijuana plants), large pots are the way to go. Larger pots will allow the yield to be maximized as much as possible when you are using the scrogging technique.
How to install your Screen of Green?
Just as important as what you buy is how you decide to use it. Some of these steps may seem painfully obvious, but you would be surprised. Trust us: it’s better to be clear. Check out these photo series by Bergmanslab.com
First of all, fill the large pots with soil after placing them inside the tent. Then put the plants into the soil and make sure they are adequately covered -- usually, cuttings that have developed a root system or plants that are roughly a month old are the best way to go.
After that, water your plants with water that is at a 6.0 pH level and doesn’t have any added nutrients. Don’t overwater them -- 8.5 ounces near the stem of your plant is perfect. It is easy to overwater a small plant in a big pot, so be sure to be extra cautious of that. All the soil in the pot should not be wet.
Next, cut a screen to fit the area of your grow room (or tent) and hang it, so it’s about 15 inches above your marijuana plants. Only do this if you have between 20 and 25 more inches of space above that, since that is where the lamp will need to hang when your plants are as tall as the screen. Use cable ties to attach the screen to allow for some movement.
Once the branches of your plants grow through the screen by four inches, begin tying it and retying it as it continues to grow. It should create a blanket of sorts at one single height.
Scrogging in 5 easy steps
1. Place a screen at 20 to 25 inches from the pots
2. Cut off the top cola of each plant
3. Prune bottom branches when top hits the screen
4. Force into flowering 2 days after pruning bottom
5. Attach all branches horizontally to the screen
Perhaps the most important thing to have with this setup is a scrog screen, generally some kind of wire or even a tight rope. A sturdy screen that can hold back the top canopy and has 2-inch by 2-inch squares built in will certainly be adequate. Screens are also the most important aspects of scrogging.
You are effectively “training” the marijuana plants to grow in your desired direction without having to do anything harsh that could affect growth adversely. The distance between pots and the screen should be 20 to 25 inches
Tip: make sure to download my free Grow Bible for more information about scrogging
This is particularly useful for individuals who either have limited vertical space or limited light emission. Having a screen over the top of the plants, keeps them lower, but it also allows the light to concentrate more evenly on each of the plants. In addition, horizontal growth will still produce useful plants in the long run.
How to scrog
But, the scrogging method isn’t all about setting up a screen and watching your marijuana grow. Although very little work is involved in general, you will still need to take great care if you want to scrog correctly.
One of the first things you’ll want to do is cut the top colas off of each plant when the plant is around 10 inches tall. This encouraged the plant to create new branches that you can manipulate in any way you please. The ideal way to manipulate the new branches is to wait until they have reached the screen. At this point, the tops of the branches will be slightly poking through one of the holes in the screen.
How to top?
You’ll want to continue to take each branch from each plant and move them over to the next hole so that horizontal growth can continue relatively unimpeded. Or bend and attach all the branches to the screen with some wire horizontally.
When to scrog
Obviously, if you let the plants continue to grow vertically, you’ll run out of space. However, if the marijuana plants are “trained” to grow horizontally, you will ultimately get more yield and a better canopy later on.
Just before the top of the plant hits the screen, cut off all the small branches and side shoots at the bottom. This give a boost to the top colas because there will be no energy wasted on the growth of useless and small side shoots and fluffy buds.
The process of taking the branches out of one hole in the screen and placing them in a hole farther away from the plant base is often referred to as “tucking.” This should be carried out with the utmost care as any breakages can cause your marijuana plants to reduce growth.
Some marijuana growers like to make their screens adjustable so that they can raise the “ceiling” if the growth becomes too abundant. This is really beneficial if you want to keep your plants in vegetative state for as long as you can.
Another way to ensure that the plants produce higher yields is by maintaining a relatively even canopy all the way across. This will involve cutting off the top portion of a plant to shorten it and also make room for deviations in the branches.
The more branches you have, the more you can continue tucking. Since the growth is diversified and the light is hitting every viable part of the plants, the yield will increase when harvest time comes around.
When to flower
Because scrogging represents an indoor growth technique, the shift between vegetative state and flowering state will be up to the individual grower. The timing should be ideal, but there are many different factors in play.
For instance, if you’re using a hydroponic system, you might be able to take the plants from vegetative growth into flowering within a matter of only 3 to 4 weeks. If the plants are in soil, it should take around 6 to 8 weeks.
Forcing flowering is something that almost takes an intuition. You can see when the plants have sort of maxed out in their vegetative state. You will obviously want to visualize how much the plants will continue to grow once they enter flowering. When you decide to go for it, put the plants on a 12/12 light regimen.
Then, growth will start to increase as the plants begin to flower extensively. Carefully train all branches and shoots through their individual slots in the screen. I always force my marijuana plants into flower just before they start to grow through the screen.
How much does SCROG yield?
So how exactly does scrogging work, and how does it actually help? The most obvious benefit of scrogging is the fact that it doesn’t waste any light at all. Energy costs money, and wasted light is a waste of yours. Because of the impenetrable blanket of leaves that you’ve created, all of the light will be absorbed by the leaves.
In addition, the plants all being the same height has a huge benefit. It allows every plant to get as much light as possible because none of the plants are shading the others, and none of the branches or leaves are being shaded.
You can also bring down the lamp to the lowest possible level (since there isn’t one taller plant that would get burned), therefore maximizing the light intensity. Of course, be sure the temperature doesn’t get higher than 77 degrees Fahrenheit!
You can see the benefit of scrogging during the actual flowering phase as well. Any branches that didn’t make it through the screen should be pruned, meaning your plant won’t develop any buds that aren’t receiving much light. That means that all of the buds will be top quality, with no fluffy or soft buds that never ripen left to waste your plant’s resources.
Ultimately, scrogging can increase your marijuana plants’ yield by up to 20%. It takes a bit of fine tuning before you’ll be consistently getting these yields, but of course the effort is certainly worth it in the end!
Some useful tips
Only use clones or feminized seeds
Only use feminized seeds and clones, since, with scrogging, it is crucial that all of your plants are female. If half of your plants were male, they would need to be removed, leaving a huge gap in the screen of green. You can see why that’s not an effective strategy.
Therefore, it is essential to ensure that you only have female plants by either using clones or by purchasing feminized seeds. Remember, you won’t know if your plants are male or female until they are into their flowering phase, so be sure to be proactive about it!
Switch to flowering stage when screen is filled
As a good rule of thumb, your marijuana plants should remain in their vegetative phase until the mesh or screen is completely filled up, without any major gaps. Your plants become the bushiest during the vegetative phase, so even though the flowering phase is the most rewarding, the vegetative phase is also extremely important.
During the vegetative phase, make sure to bend any parts that are poking their way upwards back down, so they remain on the same plane as the other parts of the plants. This will allow all the plants to grow upwards in even rows, maximizing the energy from the grow lights.
Thanks for reading. Please leave comments or questions below and don’t forget to download my free grow bible.