What is trellising?
Trellising—not to be confused with scrogging—uses string, rope, or netting to support cannabis plants as they grow big and tall so branches don’t snap. When weed plants start to produce buds, branches will get heavy, so they may need structural support, especially if you live in a place with high winds.
Why trellis marijuana plants?
Trellising marijuana plants has several benefits:
- Branches get structural support, so heavy buds don’t weigh down the plant and snap branches
- It makes plants easier to work on because branches are more spread out
- Light can hit more branches, therefore producing more buds and higher yields
- Air can flow through the plant more, helping to reduce mold and pests
How to trellis marijuana plants
Monitor your cannabis plants as they grow and get big. Err of the side of more support—if you’re not sure if a branch is going to break off, trellis it anyway. Trellising line and stakes or posts to support it are cheap, and nobody likes losing buds.
Trellising marijuana outdoors
When growing cannabis outdoors, the easiest way to support branches is to buy a tomato cage or some other pre-made structure and put it around the cannabis plant when it is young. The plant will grow into it and as it does, you can help branches along by pulling them through different parts of the cage.
Another trellising method that can be used outdoors includes using wooden stakes and plant tape. Drive a stake into the ground, stretch out a branch of cannabis, and secure the branch to the stake with plant tape. You can also use this method in combination with a tomato cage.
Depending on how big your marijuana plants are or how many you have, it may be easier to build a frame or set posts around all the plants. Outdoors, you can drive T-posts or large wooden stakes into the ground to form a rectangle around the plants, and then fix trellising line to the posts in a way that holds up branches.
Make sure to set lines tight to keep branches from hanging. If branches get too heavy as time goes on, you may need to add a second trellis line.
Trellising marijuana indoors
You can build a frame or structure around plants when growing cannabis indoors too. A common indoor trellising structure is a frame made out of PVC pipe. You can also affix a set of posts of some kind to any structure sturdy enough to support a screen—another common setup is to nail some 2x4s upright into a plant tray.
As with outdoor trellising, tie trellising line around the posts or frame in a way that supports branches.
Trevor Hennings contributed to this article.
Read more of Leafly’s guide to growing marijuana
- How to grow weed: Basics of growing marijuana
- 4 stages of marijuana plant growth
- Marijuana plant anatomy
- How to grow weed indoors
- How to grow marijuana outdoors
- Cannabis seeds 101: How to grow marijuana from seed
- How to clone cannabis plants
- Marijuana seedling and plant care
- How to harvest marijuana plants
- Troubleshooting common cannabis plant problems
- Buyer’s guides for cannabis seeds and growing equipment
- How to grow marijuana using hydroponics, aeroponics, or aquaponics