Screen of Green, or SCROG is a method of growing by which you can prune and train a plant to grow by using a screen which is placed above the seedlings. You can see instructions in the video below, and this technique is definitely not for the noob grower. While it can be learned quite easily, there needs to be some confidence with plants, and bending and tying them without fear in order for the technique to work.
So, in SCROG systems you are generally going to want a plant which produces big buds, but doesn’t get too tall and dangly. For this reason many of the sativas are out since they have a tendency to stretch. However, with practice, it should be noted that you can SCROG any plant you wish. It all comes down to learning the strain, growing cycle, and your lights ( which need to be stupid close to avoid stretching) . However, I think there are some strains which do better than others. White Widow, Northern Lights, and Skunk ( all classics I know) are all known for their dense buds and ease of grow. I’m still a big proponent of Northern Lights myself, but was pleasantly surprised that White Russian is also a real performer. Also in the running is Cheese which have a tendency to want to branch out.
As with any medical grow, your needs are really what should be paramount. Finding the right strain for your needs is what it’s all about. And if you’re looking to grow the max amount of plants but stay within the legal limit by SCROGing them, then by all means use the method on whatever plant you’re comfortable with.
For me. White Russian really was a winner for a lot of reasons. It’s an indica heavy strain which isn’t too “couch locky” and is energetic. It’s also quite strong ( 22% THC makes it one of the most potent plants ever recorded) so the amount you need to smoke is minimal which increases yield in other ways. As with everything it’s best to experiment with your set up and find out what works best for you.