pot plant leaves curling down

Marijuana Leaves Curling – How to Fix Them

Growing marijuana may seem to be easy, but sometimes problems arise that can hamper its growth. Then we ask ourselves, what might have caused this problem and what we need to do to prevent them.

As your marijuana plant starts to grow and develop, it will also grow its leave and grow in height. Perhaps one day, you wake up and see that your plant’s leaves are curling, then something is wrong. You need to know what’s the matter with marijuana leaves curling and how to fix them.

What is “clawing”?

“Clawing” is the term given when the cannabis leaves are curling up and down. This phenomenon is also called “The Claw”. Clawing happens because of several reasons, and as soon as it happens, your plant needs special attention and must be cured, or else it will hamper its growth, or it might die.

What are the reasons why marijuana leaves curling and how to fix them?

Clawing is a sign or signal that the cannabis plant is sick and needs to be healed. Seeing the leaves curling or clawing means that something is seriously wrong. There are several causes why marijuana leaves tend to curl up or down but do not worry because there are ways to cure them.

In this article, we have listed several causes of why marijuana leaves tend to curl and how to cure them.

Overwatering the Plant

We often think that when we water the plants, we keep them healthy all the time. Apparently, that is not true. If we are not careful in watering the plants, it will drown the plant’s root. Aside from drowning the plant, it will also rinse helpful microbes. Also, overwatering the plant persistently will attract parasites called Pythium, which can cause root rot. This will cause your plant to have claw-like leaves that will tell you that they are waterlogged.

To cure this, the first thing that you have to do is to try reducing the volume of water that you are giving your plant. Maintain a wet-dry cycle. You can tell by their weight if they needed to be watered. If you can pick up your pots, then it is good for you. Another method to check if your plants need water is to press the soil and see if it is dry or too moist. If it is dry then try to water them with just the right amount, if it is still too moist, perhaps do it the next day.


Feeding the plant with too much fertilizer is also not good. The excess dosage of nitrogen-rich vegetative growth base nutes can cause the plants leave to craw or to curl up and down. Overdoing any vitamin or mineral-rich feeding to the plant will cause the leaves to curl as well, and it will scorch the tips.

The best way to cure this is to have a feeding chart to control what you give to your plant. Feeding charts usually come with every fertilizer that can be downloaded on their website. It is feeding your plant with fertilizer; it is best to start low and slow. You may increase the dosage over time. Check the leaves every day to see how the plant is responding to the feeding process. Make sure to measure what you feed them having the right nutrient solution with the right pH. The right pH is about 5.8pH to 6.0 pH.

Too Hot Temperature

Heat stress is very dangerous to your plant. It can happen both indoors and outdoor cultivation, and it can even burn the leaves. You may see your plants leaves curling with brown tips. If you see these signs, then your plant may be suffering from heatstroke. This is a distress signal that you have to take notice of. The regular temperature for your plant should not be over 28 degrees Celsius, and anything above that is harmful to your plant.

To be able to cure this, make sure that you adjust the temperature to your grow room. For indoor growers, it is easy to adjust and lower the temperature. You may utilize an airconditioning unit to cool down the temperature. Unfortunately, outdoor growers may have a bit of a problem in controlling the temperature or exposure to the heat. Most cultivator uses a screen to shade to keep the plants slightly cooler.

Too Cold Temperature

Just like hat stress, very cold temperature is not also good for your plants. Cold temperature can cause curly leaves as well. Prolonged exposure to cold temperatures, which is more than 10 degrees, can not just cause curly leaves or will kill the plant. If it is caught with a high RH, buds will become moist, and I may get sick.

For indoor cultivation, if the temperature is high, just add some more grow lights to increase it. Temperature is very hard to control outdoors, though, so for outdoor growers, the best wat to deal with change in temperature is to have an early harvest. The ideal temperature for cannabis plants is 20 degrees to 28 degrees Celsius.


If you are planning to reproduce or to breed, it is very important to have healthy parent plants. Genetics will tell us that if the parent plants are healthy, it will also produce healthy offspring. In the case of an unhealthy parent plant, it will also pass on some disease to the offspring plant that would cause them to grow unhealthy as well. This may also be one reason why leaves are curling, so to fix the problem, you may need to feed your plant with much-needed nutrients or fertilizer to heal them from any kind of sickness.

Yes, growing cannabis can be easy and enjoyable, but it may also require much of your attention, especially in maintaining its health. The quality of yield depends on your plant’s health. If you happen to see that your plant is developing curly leaves, this is a sign that they are under distress. The tips that we have mentioned will help you identify which among the abovementioned factors is causing the leaves of your plants to curl. Though it can be cured, do not disregard the symptoms and do something right away to cure fix them.

Bothered of your leaves curling? Worry not & fix them now! Learn the ways on how to fix curling marijuana leaves here.

What Causes Curly Cannabis Leaves And How To Cure Them

There are numerous reasons why you might find curly cannabis leaves in your grow-op. This guide will explain why this phenomenon occurs, and what you can do to prevent it from ruining your final product.


Cannabis plants can’t vocalise a call for help—but they can send signals to tell you all is not well. If you see leaves either clawing or curling, there is trouble with the trees. Don’t ignore their pleas. This blog will help you identify the causes and cures for curly cannabis leaves.


Overwatering will literally drown your plant’s roots. Excess water will not only rinse most of the beneficial microbes from the medium, a sodden substrate can also become colonised by algae and nasty fungi. Persistent overwatering invariably invites the parasitic Pythium, better known as root rot. Cannabis plants with droopy, claw-like leaves could be trying to tell you they are waterlogged.

“Water mould” microorganisms are just like vampires; you have to invite them in before they can do any harm. Keep them out of the garden by making sure they are not welcome. Maintaining an effective wet-dry cycle is all it takes. If you can pick up your pots, do it. Then you can tell by their weight when it’s time to water.

If you can’t lift the containers, then consider a moisture meter and make sure to carefully monitor post-watering plant behaviour. Try reducing the volume of water. Alternatively, take longer intervals between waterings. Unfortunately, Pythium is virtually incurable and will turn your plant’s roots into brown sludge. If you see droopy, curly cannabis leaves, especially with young plants, look to the roots for answers.


A heavy-handed approach to nutrients is ill-advised. Excessive doses of nitrogen-rich vegetative growth base nutes can cause clawing in leaves. Sometimes, they will even canoe. Similarly, overdoing it with the phosphorus and potassium during flowering will cause curly cannabis leaves and scorch the tips. Chlorosis is a common symptom in both cases.

Dial in feeding. Easier said than done right? Wrong! Almost every brand of well-known cannabis fertiliser offers a feeding chart free to download from their respective websites. Granted, not all cannabis varieties will respond in the same way to fertilisers.

It’s better to start low and go slow. You can incrementally increase doses without seeing leaves curling or clawing. But if you dive right in at maximum strength, you can expect plenty of curly cannabis leaves that will probably die and eventually drop-off.
It should go without saying, but we’ll say it again for good measure; make sure the nutrient solution is the right pH. That’s about 6.0pH for soil and a more precise 5.8pH for coco/hydroponics.


Heat stress can occur indoors or outdoors. If you see curling and nasty-looking brown fringing, your cannabis leaves are sending you a distress signal. Cannabis plants can photosynthesise efficiently at moderate temperatures up to 28°C. Anything above 30°C and your plants are in the danger zone. Combine this with low RH and you’ve got real problems. New leaves will grow gnarly and old leaves will curl yellow and maybe even burn to a rusty, brown crisp.

Indoor growers must constantly maintain the optimal environmental conditions. This starts with optimal light distance. The only way to keep the plant canopy in the sweet spot is to measure and adjust until mature plants peak in height during mid-late bloom, depending on the strain. Moreover, indoor growers can utilise air-con and fans to keep the grow-op cool.

Outdoor growers confronted with heat waves and drought conditions have less control than the indoor grower. Constructing a simple screen shade will keep plants slightly cooler and may prevent leaves from fraying and curling further. You can’t really revive scorched leaves and will have to remove older foliage beyond saving. Also, planting in white pots instead of black pots will keep the root zone cooler.


Cold temperatures can cause curly cannabis leaves too. Eventually, all kinds of leaf discolouration will develop. Sure, cooler nighttime temps late in bloom can add a dash of purple charm to buds, but prolonged exposure to temperatures below 10°C will kill your plants. Flowers will be loose and leafy if plants even make it to harvest. Coupled with high RH, buds will be moist and become vulnerable to Botrytis, AKA bud rot.

Indoors, if temps are too low, you can always add more grow lights and turn a negative into a positive. Outdoor growers might consider an early harvest, or if possible, moving plants indoors at night. Cannabis is a hardy plant species, but outside of the optimal 20–28°C temperature range, leaves will curl or claw.


Genetics are the cause of all kinds of cannabis leaf deformities and mutations. Some strains occasionally have a tendency towards curly leaves or other odd traits. Most growers will thin out these plants. All the shrewd cultivator can do is write it off as bad luck.

Sativa strains and many autoflowering varieties are sensitive to high doses of fertilisers. This is a trait that can cause problems for beginner growers. The solution is to research your reefer. Always find out as much as you can about the genetics of a strain before you decide to grow it. Curly cannabis leaves can be completely avoided if you know how to keep your plants healthy.

Cannabis leaves curling or clawing are signs your plants are suffering. Something is going wrong in the garden. This blog will help you save the stash. ]]>