You may have heard about many different methods of growing cannabis that promise you a huge yield in reward. One of the more efficient and cost-effective methods of growing weed indoors is to employ a screen of green setup.
The Screen of Green, or SCROG, is a method of growing marijuana (mostly indoors) that can bring you much higher yields compared to growing the same strain in a traditional way. The key idea is to install a horizontal screen above your garden (you can use this method even for a single plant) and make sure that the branches spread along a plane. This kind of technique stimulates the bud formation on top of the branches that would be otherwise neglected or too overshadowed.
SCROG is a method of choice for the growers who have limited vertical space, who use, for instance, old fridges, grow tents, cabinets, containers, or other similar equipment. This method can also reduce your electricity expenses as it allows you to use power in a very efficient way. Plus, SCROG is extremely rewarding. It is more complicated that the usual way of growing marijuana in a pot, but it can give you at least a double yield in the end.
This method allows to use limited vertical space with maximum efficiency. It also requires less light than other methods, and works best with LED grow lights or CFL grow lights.
When using usual HID or HPS lights, you should take in account the heat they produce, and install the light bulbs at a certain distance from the plants. For instance, a 250W HPS bulb will work best when the plant is situated 20 inches below the light source. At the same time, LED and CFL light bulbs can be installed as close to your garden as you want it.
The most important part of this technique is a screen. You can use garden netting, poultry netting, or you can make a grid yourself. Basically, any screen is suitable as long as the holes are around 2 inches (5 cm) square. The screen should be quite sturdy to hold all your plants. Fit the screen into a frame and install it 8 12 inches (20 30 cm) above the growing medium. You will need this space to reach all the branches with your hands and keep an eye on them so no pests or rotten branches can spoil the plant.
The size of the screen, obviously, depends on the quantity of marijuana plants in your garden and of the strain you have chosen. In most cases, 4 square inches of screen per plant is enough.
The optimal size also depends on how long are you going to keep your plants vegging before switching into 12/12 light regime: the longer you are waiting, the more branches you get and, therefore, the more space you need for every plant. Generally, it is recommended to start flowering when 40-60 percent of the screen is already covered with leaves. Do not wait until there is no space left, as after switching to 12/12 lighting, marijuana will keep on growing.
As you transfer your little seedlings to the container that you will use for SCROG technique, the tops of the plants will probably already be taller than the screen level. The plants will try to go through the hole and keep on growing just like usual. That is not what you want, so gently tuck them back under the screen and align the main stems horizontally. This will stimulate side branches to grow high.
Try to direct the tops to the empty spaces in the screen. Do not try to create a dense field of leaves, as they will not have enough light after you start the flowering mode.
The more leaves grow above the screen, the more shadow they cast. Therefore, you need to be extra careful to prevent mold from appearing below the screen. Remove all leaves, dry and alive, under the screen, pinch away all the little buds, let there be only the bare stems and branches.
To prevent mold, you can also direct an additional fan to the area under the screen. This is especially essential if you are using MH or HPS lights that make the air hot and humid. If you cannot install LED lights over the whole garden, put at least a small line of LED lights under the screen to decrease the likelihood of pests and mold appearing.
You can always try to grow your favorite strain this way (we would recommend to try with a single plant at first, before taking a risk with the whole garden). But if you do not have any preferences, you may choose one of the following strains that have already proven themselves good in growing with SCROG technique:
Royal Dwarf (indica)
Durban Poison (sativa)
Super Lemon Haze (hybrid)