SCROG (Screen of Green)
Definition: SCROG, short for screen of green, is a training method that uses a horizontal net or screen stretched above the plants. As branches grow through the mesh, the grower tucks them sideways to fill every square, building a flat, even canopy where most bud sites sit at the same distance from the light.
How SCROG (Screen of Green) works
A SCROG turns a few plants into a single, level layer of colas. Because light intensity falls off quickly with distance, putting every top at the same height means each one gets a similar share of the lamp’s output.
Setting up the screen
- Mesh: 2 x 2 inch to 3 x 3 inch squares, trellis netting or a rigid frame.
- Height: about 8 to 12 inches above the top of the pot.
- Plants: 1 to 4 per tent, usually photoperiod strains, since you control how long they veg.
Filling and flipping
Each time a shoot pokes 2 to 3 inches through the net, bend it under and over to an empty square. Switch to a 12/12 light schedule when the screen is about 70 to 80 percent full, because the flowering stretch fills the rest. Keep tucking for the first 2 to 3 weeks of flower, then let the tops grow straight up.
Below the screen
Anything under the net gets little light and turns into small, airy buds. Most SCROG growers clear that zone with lollipopping around the flip, which also improves airflow at the base.
Pros and cons
SCROG makes excellent use of light in small spaces and keeps plants at a fixed height. The downsides are longer veg time, plants locked in place for the rest of the grow, and harder access for watering and inspection. Autoflowers can be scrogged, but their short timeline leaves less room to fill the screen.