How To Increase THC Production

Growing can be a little unpredictable, especially if you are new to it. As you get used to growing you can start improving the quality of your plants, you can start growing more plants at once and even increase your yields. But did you know that you can also increase the THC level in your crop? No matter the strain there are a few simple ways that you can get a better high out of your plants. This is especially good if you are starting to increase your tolerance and need something a little bit stronger. Also for anyone who is using cannabis medicinally increased THC can make the weed much more effective. Boosting THC can make strains more effective for issues such as insomnia, nausea, pain, muscle spasms and so on. So what do you need to do to increase the THC levels in your plants?

Keep Your Plant Healthy

This may seem like an obvious part of growing but the healthier your plant is the better it will be at producing THC. If you let your plant get low on nutrients, take on pests or mould, overdose on nutrients or give them excessive light they will focus on staying alive rather than producing THC crystals. If a plant is trying too hard to survive that’s all it will do. There are a number of things you can watch out for that may indicate an unhappy plant. Leaf colouring is extremely important. If your leaves are covered in little spots this indicates disease or a bug infestation. Yellowing means your plant is low in nutrients or too hot. If the leaves are dark and wilting slightly they may be experiencing nitrogen toxicity. These are just a few of the ways you can tell that your plant is in trouble and you should immediately take action to fix the issue. Make sure that the lights aren’t too strong or too close to the plant as this can burn the leaves. 

A Little Bit Of Stress

If you stress your plants just right before harvest they can start to produce a higher amount of THC crystals. You can achieve this stress by lowering the temperature or the humidity. Don’t go over 15 degrees C, just enough to make your plant panic but not hurt it. This will cause the plant to become defensive which often results in increased resin production. 

Harvest At The Right Time

This may also seem obvious but too many growers harvest early and reduce the crystal production. This will also reduce the yield and overall quality of the plant. Really we should wait as long as we can before harvesting. After the flowering stage, there is a space of a few weeks when the plant will have reached maturity. At this point, your plants will have produced the maximum amount of THC. When I say we should wait as long as possible I really mean in this 2 – 3 week range. After too long the high will become softer and calmer. This is because if we wait too long the THC will lose potency. 

Watch Your Lights

Just like any other plants cannabis needs plenty of light to thrive. A decent amount of light during the flowering process will help the buds increase in size and potency. There are a few different ways that you can ensure your light levels are helping the THC. Many growers suggest using strong UV lights to ensure that you are mimicking the sun as much as possible. Some of the most potent strains come from areas where they are exposed to a lot of sunlight, often high up in the mountains. There are those who suggest buying special lights to try and increase THC. In fact, some growers have said that you can use a specific type of grow light to increase resin production such as LEDs with a large light range. However, it is unclear whether these lights will increase the THC production or just the overall yield. 

Cure Correctly

We all know that curing is an extremely important part of the cannabis preparation stage. What we know a little less about is how curing affects THC levels. There are some schools of thought that suggest curing properly improves the cannabis overall which includes the levels of THC crystals and the potency of the buds. If the buds are not properly cured they may smell unpleasant and produce a strange high that is a bit more speedy but not as intense or enjoyable. It can also cause headaches and anxiety. Make sure you fully research the final stages of drying and curing before you start growing. 


Finally, the easiest way to make sure your plants are high in THC to start with is by choosing THC rich genetics. There are many plants that produce higher levels of THC and are naturally stronger than other strains. Starting with a high THC strain will, obviously, give you a much better starting point for using your other newfound THC increasing skills. Unfortunately, if you grow a low THC plant there is only so far you can actually increase the cannabinoid. Starting higher means being able to push it further. There are a number of high THC strains available and you can find a list of the highest THC strains on our blog. 


There are no absolutely sure-fire ways to improve the amount of THC your plants will produce. They are plants and so there is a certain amount of unpredictability involved. However, if you follow these steps you will massively increase the likelihood of high THC plants. There are quite a few rumours out there of other ways to increase THC that do not work. For example, you should not water your plants with orange juice and you definitely should not boil the roots. I’m not totally sure where these ideas came from but they are a quick way to just murder your plants. Happy growing!

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Photo by Esteban Lopez on Unsplash