How and When to Defoliate Your Cannabis Plant?

As you progress from a beginner to an experienced grower, you cross many milestones — techniques that improve your plant's health and yield. 

You learn about training techniques, and while some of them may be easy, others could be slightly intimidating. For beginners, one major milestone is low-stress training that helps improve the yield a bit. Even topping is pretty simple. All you need to do is cut off the tip, and you've just created multiple colas. Easy right?

Another easy method is defoliation, which has the potential to significantly boost your plant's growth. 

However, since it's a high-stress training method, meaning your plants may struggle a bit to recover, it's not accepted as much as other methods. 

Defoliation often gets a bad rep for being dangerous, but if you're smart about it and follow the right steps, you can benefit from this method without risking your plant's yield. But how do you do that?

Here is everything you need to know about defoliating your cannabis plant. 

What is Defoliation?

Defoliation is one of the most controversial training methods you can use on your cannabis plant; many growers love this method for the benefits it brings in terms of yield improvement but others despise it for being too stressful for the plant. 

Neither party is wrong, but what exactly is defoliation?

Defoliation is the process of removing all the unnecessary foliage from the plant, like fan leaves and branches, which are either densely packed together or overshadowing other buds. 

The idea behind this training method is two-fold. One, by removing the excess foliage, your plant's aeration and light exposure are improved since the extra leaves and branches don't hamper the flow of air or light through the canopy. 

Two, it directs the plant's energy away from excess leaves and branches to those that will grow bigger buds. Essentially, it allows your plant to not waste its energy on excess foliage but focus it on the important bud sites, resulting in bigger and denser flowers. 

However, defoliation is exclusively used for indoor cannabis plants. In the wild, cannabis plants store some of their nutrients in the leaves to deal with problems like nutrient deficiencies, drought, and pest infestations. 

These problems can occur with outdoor plants but are rare with indoor cannabis plants thanks to the highly controlled environment. So, in an indoor grow room, the thick foliage becomes a burden for the plant since it is growing in ideal temperature and humidity with low risk of pests and enough nutrient supply. 

Defoliation vs Pruning and Lollipopping 

Many growers are often confused between defoliation and pruning, but we don't blame them — it's very easy to get confused since they both appear the same at the surface. However, they are quite different. 

Yes, both methods are used on indoor (often hydroponic) cannabis plants, involving selective trimming of the plant foliage, but it's important to understand how both techniques differ from each other. 

Pruning is a similar high-stress training method that involves trimming selective branches and plants to shape the cannabis plant. On cannabis plants, pruning is used to stimulate new growth and encourage the plant to grow in a certain way that will improve the quality, yield, and energy distribution of the plant. 

On the other hand, defoliation is the process of selectively cutting off leaves (and sometimes branches) from the cannabis plant. Here, the idea isn't to shape the plant but rather to remove any unnecessary leaves to improve light and air penetration and increase nutrient concentration in the remaining parts of the plant. 

Another training method that many confuse defoliation with is lollipopping, but here, the difference is quite clear, unlike pruning and defoliation where the lines get blurry. 

Lollipopping is a high-stress training method that involves pruning the lower branches since they tend to grow smaller buds anyway. This allows the cannabis plant to focus its energy on the higher branches that grow bigger buds, and while it may seem counterproductive, it does increase the plant's yield. 

On the other hand, defoliation is not limited to lower branches. Depending on your preferences, goals, and your plant's structure, you can use defoliation on any tier of branches as long as you have a good reason that they are bundling up together and reducing light and air penetration within the canopy. 

What are the Benefits of Defoliating Cannabis Plants?

Defoliation is an excellent training method as it can bring many benefits to the table for indoor cannabis plants. Let's take a look at some of the biggest benefits of using the defoliation training method on cannabis plants.

• Better Nutrient Concentration 

As mentioned earlier, defoliation allows your plant to use its nutrients in a much better way. Indoor plants have a limited supply of nutrients, but they have a benefit that outdoor plants don't — the environment is perfectly tuned in and highly controlled, and they don't run into problems like nutrient deficiency, extreme environmental fluctuations, or pest infestations as much as the outdoor plants.

In such a scenario, defoliation allows you to take a safe gamble and improve your cannabis plant's nutrient usability. By removing unnecessary foliage, your cannabis plant no longer has to waste its energy on leaves and branches that won't grow buds. Instead, it can focus its energy on branches that promise the biggest buds. 

• Better Light and Air Penetration 

Your cannabis plant uses photosynthesis to produce energy, and this process requires a rich supply of air and light. However, some cannabis plants tend to grow dense foliage where light and air do not always pass through. 

In such a case, the leaves on the outer edges of the plant have excellent light and air exposure, but the leaves on the interior or lower branches may not get a lot of light or air, leading to poor energy production. 

Thanks to defoliation, you can prevent this problem by removing leaves and branches that are hampering the flow of air and light through the foliage. This will optimize energy production for your cannabis plant. 

• Lower Chances of Mold 

Dense foliage not only prevents light and air from getting through, but also builds up humidity within the canopy — that's a recipe for mold, and mold is never good for the cannabis plant. 

Mold can affect the plant in many ways, sometimes, even killing it, but if it doesn't kill it, it can quickly spread to the buds and make them useless for the grower. Moldy buds are nasty and dangerous to smoke. 

So, by improving the airflow within the canopy, defoliation can go a long way in preventing mold in cannabis plants that are more at risk of this problem. 

• Faster Plant Growth 

When you cut off the unnecessary leaves from your cannabis plant, it can focus its energy on important branches while getting better air and light exposure. As a result, your plant will grow faster and healthier — as long as you give it enough time to recover from the training stress.

• Better Yield

The result of improved nutrient concentration, light and air penetration, lower mold chances, and faster growth is simple to understand — drastically better yield. If you want to maximize your cannabis plant's yield and ensure it grows big and dense flowers, defoliation is an excellent method that can help you get there. 

What are the Disadvantages of Defoliating Cannabis Plants?

While defoliation is an excellent training method that can significantly boost your cannabis plant's yield, it does bring several risks that you must consider before even picking up your gardening scissors. Here are the risks of defoliation on cannabis plants.

Defoliation is a high-stress training method that can cause a lot of stress to your cannabis plant. So, if you don't follow the steps carefully, it is very easy to hurt your plant and cause irreversible damage that can lead to stunted growth or lower yields. 

Sometimes, defoliation can also backfire and expose your cannabis plant to sunburn or light stress. Since it improves light penetration in the foliage, if you don't set the lights correctly or prune too many leaves, your plant can experience light stress. 

Similarly, defoliation does affect your cannabis plant's natural defenses — it weakens them due to the removal of excess leaves. So, unless you have the bases covered for preventing pests and diseases, you should not defoliate your cannabis plant. 

Also, don't underestimate defoliation. It may seem very simple at first but you may get it right only after you've experimented with several plants. For beginners, it just won't be so simple. Defoliation is an advanced training method. 

So, should you use defoliation on your cannabis plant? Here are some situations where you should avoid defoliating your cannabis plant:

• Your cannabis plant is still a seedling, i.e., young and fragile — this training method can cause a lot of damage that can't be reversed 
• Your cannabis plant is in its late flowering stage, where the stress can reduce the quality of the buds — it's too late to use defoliation now 
• Your plant is not healthy in the first place and is dealing with diseases, pests, or nutrient issues — defoliation can amplify these problems 
• You are not an experienced grower — defoliation is a high-stress training not suitable for beginners who are just starting to grow cannabis
• You are growing autoflowering cannabis — these cannabis varieties don't have enough time to recover from the stress, so it's best to avoid defoliating autoflowering cannabis 

Using defoliation is like investing in stocks. The risks are higher but so are the rewards. So, if you play your cards right and use defoliation smartly, you can reap the rewards of a much better yield than ever before. But if you make mistakes and aren't careful enough, your plant's yield will be subpar and unsavory. 

How to Defoliate Cannabis Plants?

If you want to defoliate your cannabis plant properly, the most important step is to know what leaves and branches to cut and at what time. But there's more to defoliating cannabis plants than simply cutting the leaves. 

Ideally, you should defoliate your cannabis plant twice: once during the vegetative or growth stage and once during the flowering stage. However, if you are new to training cannabis plants and don't have a lot of experience, you should stick to defoliating it during the vegetative stage only. 

So, how do you defoliate cannabis plants? Read on to know. 

• Choose the Right Cannabis Plant 

The first step in defoliating the cannabis plant is to determine if your cannabis plant can even handle this high-stress training method. As mentioned earlier, defoliating puts a lot of stress on your cannabis plant, and not every plant can handle this training method. 

So, you should only use this method on completely healthy cannabis plants. The plant should be sturdy and strong, have green leaves, a good growth rate, upright stems, and the medium should be healthy, too. 

If your cannabis plant does not look healthy — it is frail, shows signs of nutrient or watering problems, is home to pests, or suffering from any diseases — avoid defoliating your cannabis plant. Here, the training method will only make matters worse. 

Outdoor cannabis plants already go through some levels of stress due to the natural environment, which is unpredictable and less controlled. They store some nutrients in their leaves due to this stress.

On the other hand, indoor cannabis plants live in a highly controlled environment where the only reason they will suffer from stress is down to grower error. So, there's no point defoliating an outdoor cannabis plant — stick to indoor plants only. 

Another reason why outdoor cannabis plants don't need to be defoliated is because the sun moves from one side to the other, so most parts of the plant get adequate exposure to light anyway. Defoliation is not going to make much difference. 

At the same time, you should only train plants with a long growth cycle. Plants that grow really fast or autoflowering strains are not suitable for defoliating since your plant will take a long time to recover from this HST method. Autos and fast-flowering plants don't have this luxury. 

• Vegetative Stage

Once your cannabis plant is well within the vegetative stage, you should defoliate it for the first time. Ideally, you should defoliate a vegetative cannabis plant right before you switch the light cycle to 12/12. 

Here, you should begin defoliating the big fan leaves that are the size of your palms. These fan leaves are notorious for blocking light from leaves under them while also reducing aeration. These should be the first to go from your cannabis plant. 

Next, you should remove any leaves that are growing toward the foliage's interior — these leaves will also overshadow bud sites under them and won't get enough light or air anyway to produce more energy. 

Then you should cut away any old leaves that are turning yellow or brown. These leaves hardly produce energy and instead, they suck more energy than they produce. 

If you are new to high-stress training, it is recommended that you only cut away the bottom half of your cannabis plant — up to the first four nodes from the bottom. This is because these branches tend to grow smaller buds anyway, so even if you make a mistake, the severity of it will be minimized. 

Also, never overdo your cannabis plant. A healthy cannabis plant can survive an aggressive defoliation of 20% to 25% but we recommend only defoliating 10% to 15% of the plant to be on the safe side. And when in doubt, you should always take a conservative approach. 

Once you defoliate your vegetative cannabis plant, you should give your plant a few days of rest before switching the light cycle to 12/12. This should be enough for recovery. And if you want to go a step further, you can also pair this method with pruning or lollipopping. 

• Flowering Stage

You should also consider defoliating your cannabis plant once more during the bloom stage. This should be done when your cannabis plant has already been flowering for three weeks. 

Once your plant enters the second half of the flowering stage, you should avoid defoliating it unless you have a strong reason and enough experience to do so. Your plant needs to focus its energy on resin production, not recovering from stress. 

Here, you must take the same approach as you did during the vegetative stage but you need to be more conservative about the leaves and branches you remove. Intermediate growers should stick to removing big fan leaves and experienced growers can push their luck a bit, but beginners should be super cautious. 

You will also be handling your cannabis plant a lot more during defoliating. While it may be alright to do so during the vegetative stage, it can disturb the plant during bloom. So, be very careful while handling your cannabis plant when cutting the leaves during bloom. 

Once you have defoliated your cannabis plant, you must continue watering it as usual. Your natural instinct would be to give it more nutrients or take more care of it, but your plant will get through it without much fuss — just keep an eye on it and check for any problems. 

There are some cases where you should avoid defoliating cannabis during its flowering stage. First is if you are a beginner — this is a meticulous process and can significantly affect your plant's flower production and yield if you mess up. 

Also, you should avoid defoliating your cannabis plant during bloom if it has a short flowering cycle or if it is recovering from nutrient issues, watering problems, pest infestation, or other diseases. 

How to Know What to Defoliate on a Cannabis Plant?

You'd be surprised that as stressful a method as defoliating is, there are no definitive rules you need to follow. You have to follow your gut instinct (and logic) to know which leaves to cut off and how many you can cut off. 

Again, if you are a beginner, you should start from the bottom and only cut leaves on the lower branches of your plant. This will give you some room for error. As you progress, you will quickly learn which leaves to cut and which ones to not — it comes naturally after a while. 

The process of cutting the leaves is also quite simple. Keep these things in mind:

• Always use sharp gardening scissors to make clean cuts 
• Always disinfect your scissors with alcohol before using them to prevent infections 
• Wear gardening gloves to protect your plant and your fingers 
• Avoid using your fingernails to cut the stems — this can lead to improper cuts and infections 

Here are some other tips you should keep in mind when defoliating your cannabis plant:

• If you are defoliating, you should try to make your cannabis plant grow flat and wide — this type of canopy offers the biggest harvests
• Start slow and low if you are a beginner — as you go upwards on the plant and defoliate more, the margin for error narrows down and the process becomes less forgiving 
• Read up on your strain's resilience before defoliating it — some strains may not be able to handle it even if they grow big and have a long growth cycle 
• Use curved trimming scissors for a comfortable defoliating experience 
• Only defoliate up to 15% to be on the safe side

Summary: How and When to Defoliate Your Cannabis Plant?

Defoliation is a high-stress training method that involves selectively cutting off leaves (and branches) of the plant to improve aeration and light penetration within the foliage of indoor plants. This training method can significantly boost your cannabis plant by improving nutrient distribution, light and air penetration, and boosting growth. 

But it is not for everyone and every cannabis plant. Beginners should stick to low-stress training and defoliation shouldn't be used on plants that are not 100% healthy. It's a stressful method that can hurt the plant and exaggerate any problems the plant is already facing. 

So, if you want to defoliate your cannabis plant, make sure it is healthy and fit to survive this training method. Then, use sharp gardening scissors to cut off any leaves that are hampering light penetration and aeration within the foliage. That's it.