Cannabis defoliation is a growth technique base in removing leaves from the plant, varying its vegetative process. Defoliation applied to cannabis growth consists in removing leaves off the plant in certain stages of growth, with the goal to get more quality and quantity per harvest. Many growers believe defoliation can be used as a tool to increase cannabis yields indoors, but there are also a lot of cannabis growers who say that plucking leaves off cannabis plants (defoliation) is not beneficial for your cannabis yields in any way. It is a form of “stress,” but it produces positive results. However, it is not a method that you should rely on as a newbie.
The way to start is to first remove shabby leaves. Then it gets down to a bit of artistry. The idea is to remove the leaves that will impede bud growth. This also means removing upper leaves if they threaten to shade too much below. However, a lot of defoliation occurs on the bottom branches of the plant. Especially when growing indoors, the buds at the top of the canopy receive optimal light.
This pruning process will not only help shape the growing plant, but also promote dense and thick bud growth in all the right places.
There are many different techniques for shaping plants depending on the conditions of the grow operation. This is where experience comes in. Growing your plants on a southern, exposed slope is one of the other ways to assist this process. The pruning you would do here is partly determined by the grow environment. Outdoor crops are defoliated differently, of course. The only light source is the sun.
You should start by taking off troublesome fan leaves (big leaves with many “fingers”). You’re looking to remove leaves that are laying on top of each other. When possible, try to take leaves lower down on the plant, and in the middle of the plant. For most indoor growers, this means removing “distractions” lower down on the plant. This encourages the plant not to waste resources on a node which is only going to produce “popcorn” buds. Try to avoid plucking the outer and uppermost leaves. You want a plant with leaves around the outside, and fewer leaves in the middle or bottom getting bunched up and touching each other. When defoliating, take 20% of the leaves at most in one session.
Why defoliate in the Vegetative Stage?
- Prevent Mold – Defoliation can help prevent mold from growing on a leafy plant.
- Faster growth in the parts of the plant you want
- Makes a more compact plant- the plant tends to start growing more horizontally instead of upwards, helping you create a wide plant with a flat canopy
- Defoliation can help you create a better structure to start flowering by allowing you to create several main colas, and get rid of colas that are unlikely to produce any significant amount of bud.
- Training is easier
When to defoliate
- Plant has several nodes
- Plant is healthy and fast growing
- Hardy strain
- Plant is so leafy that leaves are laying on top of each other, especially if it’s leafy in the middle of the plant, preventing light and air circulation from getting to the inside of the plant
Cannabis plants seem to spend the most energy on buds which are exposed to light, and those are the buds that grow the biggest and the most dense. I believe that’s why buds hidden from view and in the middle or bottom of the plant never seem to fatten up – they don’t get enough exposure to light and air.
Why defoliate in the Flowering Stage?
- Helps prevent mold and bud rot on indoor plants by reducing humidity inside the plants
- Bigger yields
When to defoliate in the flowering stage
- Plant is healthy and fast growing
- Plant has been hardy
- Plant is so leafy that leaves are laying on top of each other
- Buds are hidden from the light by large fan leaves
Your main goal with defoliation in the flowering stage is to expose all your main buds to light and air. Exposed buds simply grow faster and fatten up faster than buds that have been hidden by leaves. Try to focus on removing the bigger fan leaves. As in veg, you should still be removing any leaves that are laying on top of each other, and focus on removing those lower leaves on the plant if possible. This defoliation will decrease the chances of mold and help release energy to be put into the colas.
You especially want to remove any big fan leaves near the top that are hiding buds from the light. If a fan leaf is yellow, it doesn’t really have anything left to offer the plant, so it’s also important to take these fan leaves at the top of the plant if they’re blocking any buds.As always, never take so many leaves that you can fully see through the plant. Plants in the flowering stage don’t really grow more leaves, so all the leaves you take are gone forever and the plant won’t replace them! Taking too many leaves in the flowering stage can seriously hurt your yields, and no one wants that!
Most Common Mistakes
Plucking the Wrong Leaves
Defoliation is meant to open up the plant so more light can get in. This is accomplished by removing fan leaves and fan leaves only! Pulling sugar leaves, or growth tips can mean less bud, lost bud and/or slower growth for that part of the plant.
Pulling Leaves Too Early
Younger plants, especially those grown in hydroponics under a metal halide, tend to take on a shorter and bushier look than if they were grown otherwise. When you see what looks like a little shrub packed with cannabis leaves, your instinct may be to pull some, but you’ll need to make sure to factor in the age and health of the plant before moving forward. If you pull leaves from a plant that’s sickly, small, has only a few leaves, or is just plain bad at recovering, you’ll be waiting for days or even weeks before your plant bounces back from the procedure.
First Time Grower
Again, defoliation is not a good idea for beginners. It is far more important to hone other aspects of your grow techniques first. Make sure you have a decent grow space. Water and feeding is really important. Of course the lights – both placement and timing – are a big part of making sure you have a successful grow.
Cannabis defoliation is a quite easy process, but it has its own risks. Take your time, and be precise with your scissors. A wrong cut could harm future shots. Some growers choose to do aggressive defoliations, leaving the plants almost naked, while others just remove few fan leaves. If this is your first time, trim just the big fan leaves, so you learn the technique slowly learning the results of each action. Remember you will always have options to remove more leaves, but once you trim too much there is no way back. Removing too many leaves could be definitive to your plants.