Use a 36 x 36 inch (91 x 91 cm) SCROG screen for a 3x3 grow tent, trimmed down to roughly 34 to 35 inches square so it clears the corner poles and leaves a 1 inch gap for airflow. Pair that footprint with 2 inch mesh spacing, which creates an 18 x 18 grid of openings and plenty of tie points to spread a canopy flat. Mount the screen 8 to 12 inches above the top of your growing medium.
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How Big Should a SCROG Net Be in a 3x3 Tent?
A 3x3 tent has a 36 inch by 36 inch inner footprint, so the net should match that square without pressing into the walls. Cut or buy 34 to 35 inches. The 1 to 2 inch margin keeps buds off the tent walls, where condensation and poor airflow invite mold.
Most pre-made 3x3 trellis nets ship at 36 x 36 inches with a stretchy border. They work, but the hooks can be pulled tighter to shrink the frame inside the tent.
How Many Plants Under a Scrog Screen?
What Mesh Spacing Works Best?
Two inch squares are the standard for a 3x3. They hold a main stem in place but still let you reach through to tuck shoots during stretch.
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Four inch netting suits large commercial trellis but is too wide for a small tent. Shoots slip through and the canopy stays lumpy.
If you build a PVC or bamboo frame, use non-stretch line such as masonry twine. Nylon stretches under a heavy canopy and lets the screen sag.
How High Above the Pot Should the Screen Sit?
Set the screen 8 to 12 inches above the surface of the growing medium. That leaves room to water, prune, and reach under the canopy.
In a 60 inch tall tent, keep the screen lower, around 8 inches, because flowering plants can double in height. A 72 inch tent gives you more slack.
Leave at least 12 to 18 inches between the finished canopy and the light. Anything closer risks heat stress and bleached tops.
How Many Plants Fill a 3x3 SCROG?
- 1 plant: longest veg time at 6 to 8 weeks, but the cleanest single canopy.
- 2 plants: the sweet spot for a 3x3, fills the screen in 4 to 6 weeks.
- 4 plants: fastest fill in 3 to 4 weeks, though crowded root zones need closer watering attention.
When Do You Flip to Flower?
Flip when the screen is about 70 to 80 percent full. The stretch during the first two to three weeks of flower fills the rest.
Keep tucking shoots under the net until stretch stops, then let the tops rise above the screen.
3x3 SCROG Setup Quick Reference
- Screen size: 34 to 35 inches square (36 inches maximum)
- Mesh spacing: 2 inches, an 18 x 18 grid
- Height above medium: 8 to 12 inches
- Plant count: 1 to 4
- Flip trigger: screen 70 to 80 percent full