Screen of green, or SCROG for short, may be a mystery to most people but it’s highly important for anyone who grows their own cannabis and is serious about developing a good crop. SCROG is a way of reaching an optimal yield by training plants horizontally rather than letting them grow vertically.
The good news is it’s fairly easy to set up. Even a novice can do it. All you require is a bit of space and some time and effort to set it all up.
Compared to the sea of green method (SOG) where the aim is to nurture one central bud, the purpose of SCROG is to get more light to the important parts of your plant and thus increase the number of flowers and buds that develop.
It’s a good choice because it can be used with less powerful fluorescent lights if that’s all you have.
New growers often get screen of green mixed up with sea of green or SOG. The latter is another growing technique where multiple plants are pushed together and allowed to grow vertically. It’s an ideal method if you have limited space but want to improve you yield. To implement SCROG successfully, you will need a lot more space.
What is SCROG-ing?
Basically, it involves putting a canopy over your crop and tying the plant stems to it so that they grow horizontally. This is an ongoing process as the plant develops and can take quite a lot of work. As more stems and leaves grow they have to be trained through the canopy so that you improve yields.
The canopy can take many forms. Some growers use chicken wire, others rope or even string. You want a width of about 5cm for each of the spaces so that there’s enough room for the plant to grow through and it has to be sturdy enough for your sativa or Indica strain to be secured.
Many people combine topping with their screen installation. That means cutting off the tops of plant so that they grow new branches. It creates a much ‘bushier’ plant and should lead to more bud and flower growth if done properly.
While it’s generally used by more experienced growers, SCROG isn’t terribly complicated and is well worth experimenting with should you want to improve yields.
How to Make a SCROG Screen
You can buy SCROG screens of various sizes online or at cannabis stores and they’re not very expensive. Most people, however, prefer to make their own. Even if you are not great at building things, you can set up a simple screen that should do the job.
Your screen needs to be able to cover the majority of the area where you crop is going to be grown. It also ideally needs to be light but strong and well-lit from above.
If you have enough woodworking skill, we suggest making an initial frame from light wood to act as a base. You can then tack chicken wire to it or tie rope to create squares through which your plant can grow. The good news is there are plenty of tutorials online which you show you how to do this. It doesn’t have to be perfect but it does need to be functional so bear that in mind when you are making your screen.
Building your own SCROG screen means that you have one that actually fits your space better and it is certainly worth considering if you want to save some money.
Putting Up Your SCROG Screen
The next step is to put up your SCROG screen and a lot of this is to do with height and light. You want to suspend the screen close to your light source but not so close that your plants will grow into it and get burned. The general rule should be that individual plants should have about 30 cm of screen space to give them enough room to expand.
You can also use your screen to limit the height of your plants as you will be tying them down to essentially run sideways. There shouldn’t be a problem if you are constantly checking your plants and caring for them properly.
Caring For Your Crop
Once you have suspended your screen, you can begin to train any stems that are breaking through already. Tying them with string is less damaging than wire and all you need to do is cut it when you come to harvesting your crop at the end of the flowering period.
Every couple of days or so, you will need to check your crop and pull down any stems that have made their way through and tie these down. Exposing more than just the tops of the plants to the light should encourage more flowers to form and greatly increase your crop but it can get fairly crowded on top of the canopy.
One thing you will want to do to increase yield is expose more of your plant to light. You can improve this by removing the big fan leaves which tend to form near the bottom of each plant. These have fairly low levels of cannabinoids anyway so they are not much use accept for going on your compost pile.
The thicker collection of leaves and stems that develops around your canopy means that you should also increase ventilation around your plants. This helps cut down issues such as mold developing that can damage your crop and should keep the temperature and humidity relatively even.
Should You Top Your Plants?
Topping is a way of encouraging your plant to create multiple branches. It’s also quite simple to do, you simply cut the top of the plant as it comes through. Most plants when they grow develop one main cola which is dominant over the rest the foliage. When you top the cola, you should get two stems forming in its place which means that you develop more plant to train over your canopy.
FIM-ing is a similar practice but you shave the stem of the plant rather than cutting it off completely.
SCROG vs SOG
Some newbies can get confused over the terms SCROG and SOG. Sea of Green or SOG is a cultivating process that is almost the exact opposite to SCROG. You are not looking to develop many different colas but one. It’s used if you have limited space.
First, many plants can be planted close together and you’ll be surprised at how quickly they still grow. While the buds are only formed on the one cola, you can get a pretty good yield in a much tighter space. It also makes the final harvesting pretty easy because you don’t have to spend time looking for buds.
Our Top SCROG-ing Tips
Going down the SCROG route is not rocket science and anyone can do it but there is a best practice that you should try to keep to. Here are our top tips for getting it right first time:
- Don’t bother with a store bought SCROG screen, it’s best to build your own. These are relatively easy to construct whether you’re using wood and string or simple chicken wire. You can also design that canopy to fit the space you have.
- The SCROG screen should be put up during the vegetative stage. Once your plants start flowering, it’s way too late. Some people put up their screen as soon as they germinate their seeds. Others wait until it has reach a certain height.
- Be careful when you start weaving the cannabis stems into the canopy. You don’t want to snap them. Start on the outside and weave your plants to the outer edge and then gradually move further in.
- You may want to start trimming away stems that aren’t getting any light as well as the larger leaves lower down. This just clears the foliage to allow more light to get through and increases the potential for buds to form on what remains.
- You need to keep your SCROG screen under control and, particularly in the flowering stage, there’s going to be plenty of work to do. This is an art in itself but don’t be overzealous and end up cutting away something you shouldn’t.
- Pay special attention to the air circulation around your screen as this can affect the temperature and humidity and ultimately damage your plants if you don’t watch out.
If you have plenty of space and want to produce an abundant crop, the SCROG method is certainly something you should consider. The simplicity of setting up a light screen to train your plants over means that it’s a process that even an amateur can do.
SCROG works for any strain whether sativa or Indica. Sativa do tend to grow much higher than Indica which makes them perfect for training. Build a sturdy enough screen and it should last you for a long while and can be used for multiple crops.