A cannabis SCROG setup uses a horizontal screen placed over the plants. Growers tuck growing branches under the mesh during veg so the canopy spreads flat and every bud site sits at the same height under the light. In a 4x4 ft tent, one plant trained under a screen for 4 to 6 weeks can fill the whole area.
What Is a SCROG Setup?
SCROG stands for Screen of Green. A net or wire grid stretches across the grow space, and branches grow through the openings. You bend each branch back under the mesh instead of letting it rise.
The result is a canopy with dozens of tops instead of one tall cola. Each top receives the same light intensity, so lower buds do not get shaded out.
Why Does SCROG Beat Untrained Growth?
An untrained plant sends most of its energy into one main stem. Light drops fast with distance, so buds below the top stay small and loose.
- Flat canopy: light hits every top at the same distance from the lamp.
- More tops: bending breaks apical dominance, so side shoots grow.
- Better airflow: even spacing cuts mold risk in dense flower.
- Lower height: plants stay short, which fits tents with limited headroom.
Equipment You Need for a Cannabis SCROG Setup
You need a screen, a way to hold it, and basic grow gear. Nothing here is expensive.
- Trellis net or wire grid with 2 to 4 inch squares
- PVC pipe, wood frame, or tent pole hooks to hold the screen
- Soft plant ties or garden wire for tucking
- Fabric pots, 3 to 7 gallons
- LED or HID light sized to the tent
- Inline fan, carbon filter, oscillating fan
- Timer, pH meter, nutrients
Screen and Frame Options
A nylon trellis net is the cheapest route. It stretches over the tent frame and hooks onto corner poles with clips.
Chicken wire on a wood frame holds shape better under heavy branches. The tradeoff is sharper edges that can cut stems, so sand the wire ends.
String grids built from mason line work well too. Run horizontal and vertical lines every 3 inches, then tie each crossing.
Light, Tent, and Pots
Match light wattage to the screen footprint. A 4x4 ft screen needs about 400 to 480 watts of quality LED draw.
Fabric pots air-prune roots and drain fast, which suits the frequent watering a big canopy demands. In a 4x4 tent, one 7 gallon pot or four 3 gallon pots both work.
What Screen Height and Mesh Size Should You Use?
Set the screen 8 to 12 inches above the top of the pot for photoperiod plants. That gap gives you room to reach under the net for watering and pruning.
Mesh openings of 2 to 4 inches fit most stems. Smaller squares hold thin branches in place but make tucking harder. Larger squares let branches slip back down.
Some growers run two screens: a lower one at 10 inches and a second 8 to 10 inches higher. The top screen supports heavy colas in late flower.
How to Set Up a SCROG Step by Step
- Start seeds or clones and veg them until each plant has 4 to 6 nodes.
- Top the plant above the 3rd or 4th node to create two main shoots.
- Mount the screen 8 to 12 inches above the pot rim and check that it sits level.
- Wait for shoots to reach the mesh, then bend each one back under the nearest square.
- Tuck every 2 to 3 days during veg. Push tall growth outward toward empty squares.
- Fill about 70 percent of the screen before you stop vegging.
- Flip the light to 12/12 for photoperiod plants. Keep tucking for the first 7 to 10 days of stretch, then stop.
- Remove leaves and small shoots that sit below the screen. They get no useful light.
- Hold the canopy flat through flower and let the tops rise 6 to 10 inches above the net.
Can You SCROG Autoflowers?
Yes, but the clock is fixed. Autoflowers flower on their own schedule, often 3 to 4 weeks after sprout, so you get a short veg window for training.
Use a lower screen, 6 to 8 inches above the pot, and start tucking as soon as shoots reach it. Low-stress bending works better than topping for autos because it does not slow growth.
If the strain stays short, a single screen and gentle leaf tucking may be enough.
How Many Plants Per Screen?
Plant count depends on veg time, not screen size alone.
- One plant in a 4x4 ft screen: needs 6 to 8 weeks of veg to fill the net.
- Four plants in a 4x4 ft screen: fills in 3 to 4 weeks with less bending per plant.
- Two plants in a 2x4 ft screen: a good middle ground for most home tents.
Fewer plants means longer veg and more control over the canopy shape. More plants fill faster but compete for the same root space.
Common SCROG Mistakes
- Screen too high: branches stretch before they reach the mesh and the canopy turns uneven.
- Tucking after week 2 of flower: stems harden and snap, and buds get pinned under the net.
- Overdefoliation: stripping too many fan leaves slows growth during stretch.
- Weak frame: a sagging net drops the canopy and blocks light to the middle.
- Too many plants: crowded screens trap humidity and invite bud rot.
- No airflow under the screen: stale air at the pot level encourages mold.
SCROG for CBD Hemp Flower
The same screen technique works for high-CBD hemp grown for flower. Hemp plants respond to bending and topping in the same way cannabis does.
Check your state law before you plant. Hemp must stay at or below 0.3 percent THC on a dry weight basis under federal rules, and some states add their own limits and licensing.
CBD flower from a home SCROG tends to be less dense than commercial indoor flower, so dry it at 60 to 70 F and 55 to 60 percent humidity.
FAQ
Does SCROG increase yield?
SCROG raises the number of top-quality bud sites by spreading light across a flat canopy. Some growers report large jumps in yield, but results track light wattage, veg time, and strain more than the net itself.
When do you stop tucking?
Stop 7 to 10 days after the light flips to 12/12, once stretch ends. After that, stems stiffen and bending causes breaks.
Can you reuse a SCROG net?
Yes. Wash nylon nets in warm soapy water and let them dry before the next run. Replace frayed string or bent wire to avoid snags.
Is SCROG better than SOG?
SCROG uses few plants and long veg to build one flat canopy. SOG uses many small plants and short veg. SCROG suits plant count limits, while SOG suits fast turnaround.