A plant is ready for SCROG (screen of green) when it has four to six true nodes and stands about 8 to 12 inches above the growing medium, which lands near three to four weeks from seed or one to two weeks after a clone roots. Buy the net at that stage, not after the canopy closes in. A soft nylon trellis with 3.5 to 6 inch openings stores flat, flexes when a stem pushes against it, and leaves enough room to reach through with two fingers. That last detail separates a net you will actually use from one that sits in a box. Match the net width to the tent footprint so the screen spans the full grow area, and confirm the mesh has slack. A taut, unforgiving grid bends shoots past 90 degrees and snaps them.
What the plant should show before you install a screen
Timing fails most often because growers read the calendar instead of the plant. These signs tell you the plant can handle weaving without stalling:
Best Scrog Net for Cannabis Grow: Comparison Review
- Four to six true nodes above the cotyledons, with the newest pair fully open.
- A stem that resists a gentle sideways push. Seedlings that flop over are not ready.
- Active vertical growth of about an inch per day under veg lighting.
- Clones with roots showing at the drain holes and new leaf growth on top.
- Uniform green color and no signs of nutrient lockout, since stressed plants recover slower from bending.
A plant that is leggy and stretching is a candidate. A plant that is stalled, pale, or recovering from transplant gets another week before training begins.
What to look for in SCROG gear
- Mesh opening: 3.5 to 6 inches. Narrower mesh holds more tops but makes tucking awkward with thick stems.
- Material: soft braided nylon or coated polyester cord. Bare wire cuts plant tissue and rusts in high humidity.
- Framing: a pre-framed net or a roll you stretch yourself over hooks, PVC, or a tent pole kit. Rolls let you set the exact height.
- Adjustability: clip or hook systems that let you raise the screen as the plant grows.
- Coverage: one net per grow area, with about 2 inches of overhang past the pot footprint.
- Second net: buy two if you plan on tall sativa-leaning plants. The upper net goes up during the stretch.
Sizing and timing bands that work indoors
- Screen height above the medium: 8 to 12 inches for the first net. Lower than 6 inches leaves no room for watering and inspection.
- Second net height: 8 to 12 inches above the first, installed before the stretch peaks.
- Fill target before you flip to 12/12: 60 to 80 percent of the openings occupied by a growing shoot.
- Tuck window after the flip: the first 10 to 14 days of stretch. Stop once flowers set and stems turn woody.
- Plant density: one plant per 2 by 2 feet of screen for photoperiod plants. Fewer plants spread wider give the cleanest canopy.
- Shoot spacing: one top per 4 by 4 inch block keeps airflow moving through the canopy.
Steps once the screen is up
- Set the net and let the tallest shoot grow 2 to 4 inches above it.
- Tuck that shoot under the nearest opening and guide it toward the edge of the screen.
- Repeat every two to three days, always moving outer shoots outward and letting center shoots fill gaps.
- Remove leaves that sit flat against the medium or block a bud site directly under the net.
- Flip to 12/12 once the screen is mostly filled, then keep tucking through stretch.
- Trim anything below the net that will not reach the light. That material yields little and traps moisture.
Pitfalls that cost a run
- Starting on a seedling under three nodes. The stem kinks and growth stalls for a week or more.
- Setting the net too high. Shoots stretch to reach it and the canopy turns thin and airy.
- Weaving after week three of flower. Stems harden and resist bending, so they break instead of flex.
- Filling the screen past 90 percent before the flip. The stretch adds another 50 percent of growth and the canopy crowds itself.
- Pulling leaves instead of tucking shoots. Defoliation is a separate tool with its own timing.
- Ignoring airflow. A flat canopy holds humidity under the leaves, which invites mold in late flower.
FAQ
Can I start SCROG during flowering?
Only in the first 10 to 14 days of stretch. After that, stems lignify and tucking breaks them. Late flower training is limited to light leaf removal and support.
cannabis scrog setup step by step
How many plants belong under one screen?
One plant per 2 by 2 feet for photoperiod plants, or two to three in a 4 by 4 screen. Fewer plants trained wider usually beat a crowd for light penetration.
Do autoflowers work with a screen?
They can, but the short veg window leaves little time to fill a net. Use a low screen, tuck early, and expect a smaller fill before flowering starts on its own.
What if a stem snaps while tucking?
Wrap the break with plant tape or a soft tie and support it. If the outer skin is intact, the shoot usually knits back within a week and keeps growing.
Does the net replace topping?
No. Topping creates the branches, and the screen spreads them. Most growers top once or twice before the net goes up.