You’ve spent weeks preparing for your grow, planted your seeds and watched your seedling spring into life, it continues to grow, and you are looking forward to a great harvest. Then you notice that the leaves on the plant are not looking how they should, and they are starting to noticeably droop. How can that happen when you thought it was going great? There are quite a few reasons this can happen, but don’t worry, here we’ll give you all the info you need to get your cannabis back to full health and vitality.  

Possible causes for cannabis leaves wilting and drooping 

Cannabis leaves can wilt and droop for a lot of different reasons, usually signaling an underlying issue with the plant's overall health. These issues range from overwatering and underwatering, nutrient deficiencies, pests' diseases, to environmental stress. Whatever the reason, they will be affecting the plants' ability to absorb and utilize water and nutrients. 

Overwatering 

Watering your cannabis plants incorrectly is by far the most common reason for the leaves on your plant to be drooping. Almost all growers, when they are just starting out, become overzealous with the watering can. When the soil is constantly wet, the roots can't access enough oxygen, leading to root rot and poor nutrient absorption. This lack of oxygen stresses the plant, causing the leaves to droop as a sign of distress. 

How to fix: 

If you think you are overwatering, stop. Firstly, allow the soil to dry out completely before watering again. When it's dry, feel the weight of your pot, that way you know you only need to water it again when it starts to feel like that. Ensure that your pots have proper drainage to prevent water from accumulating at the bottom, adding some stones or broken pottery to the bottom of large containers can help. Adjust your watering schedule to match the plant's needs, typically watering only when the topsoil to the depth of your finger is dry. This will help restore proper oxygen levels to the roots and improve the plant's overall health. 

Underwatering 

Underwatering is another potential cause of drooping cannabis leaves. When the plant doesn't receive enough water, the cells of the plant cannot maintain their turgidity (how rigid they are), leading to wilting and drooping leaves. Too little water also deprives the plant of the hydration needed to transport minerals and sugars and is essential for photosynthesis. 

How to fix it if you’ve underwatered your plant: 

If your plant is drooping because of too little, water your cannabis plant thoroughly until you see water draining from the bottom of the pot. Ensure consistent watering, a little at a time by checking the soil regularly and watering when the top 2 inches feels dry. Using a simple moisture meter can help you identify and maintain levels accurately. If the plant is underwatered and you give it sufficient hydration it will perk up within a few hours. 

Nutrient deficiencies / excess 

nutrient deficiency causing yellowing leaves

An incorrect balance of nutrients can cause yellowing leaves, brown patches and wilting. When the plant has the incorrect level of essential nutrients like nitrogen, phosphorus, or potassium (either too much or too little), it cannot perform vital functions such as photosynthesis and bud development. This imbalance weakens the plant, leading to drooping leaves as it struggles to thrive and can eventually kill it. 

Common cannabis nutrient deficiencies are:

How to fix: 

To fix nutrient imbalances, you must start by identifying which nutrient is causing the issue. The most critical thing is to ensure that the pH level of the soil is in the optimal range (6.0-7.0) as this will allow correct nutrient absorption. Once it is in this range, add nutrients using the guidelines from the nutrient supplier. Regularly monitor your plant's health and adjust the nutrient mix as needed to ensure your plant receives all essential nutrients for vigorous growth. 

Heat stress 

Heat stress is another very common cause of wilting or drooping leaves. When the temperature at the surface of the leaf is too high, it can lead to excessive water loss through transpiration, making it difficult for the plant to maintain its internal water balance. The lack of moisture in the plants cells results in drooping leaves as the plant tries to conserve water. Heat stress if extreme can also cause the leaves of your cannabis plant to curl up or down as the leaf dries out.

How to stop heat stress: 

To fix heat stress, ensure your cannabis plants are kept in an environment with temperatures between 70-85°F (21-29°C). Provide adequate ventilation and airflow to cool the plants and reduce the temperature. You can also use fans or air conditioning to maintain a stable, cool environment. Additionally, consider using grow lights that emit less heat such as LED’s or CFL bulb as these provide the essential light without generating heat. 

Excessive humidity 

cannabis leaves drooping from excessive humidity

Excessive humidity can cause problems with your plants' leaves. High humidity levels can make it much harder for cannabis to transpire effectively, leading to an accumulation of water within the leaf cells. This excess moisture can make the leaves heavy causing the supporting stems to droop, and it also creates an environment conducive to mold and mildew growth that can lead to bud rot.

How to fix: 

Use a hygrometer to find out the current humidity levels, then use a dehumidifier to reduce moisture levels in the grow space, aiming for a humidity range of 40-60%. Ensure proper air circulation with fans to help regulate humidity and prevent stagnant air. Monitor humidity levels regularly to ensure they stay within the stable range. By controlling humidity, you will help your cannabis plants stay healthy and prevent the leaves from drooping. 

Pests 

cannabis leaf drooping with signs of leaf miner

There are a variety of pests that can invade your crops and cause the leaves to suffer. Insects like spider mites, aphids, and thrips feed on the plant's sap. They will bite through the outer layers of the plants cells and weaken the overall structure of the plant itself. They can also leave the plants open to infection from fungal spores and other diseases. This often results in drooping leaves as the plant struggles to cope with the damage and loss of vital fluids. 

How to fix: 

Deal with any kind of harmful cannabis pests as soon as you spot them. The key to this is to regularly inspect your plants for signs of damage or discoloration, eggs or webs. Use organic insecticides or neem oil to treat infestations depending on the culprit. Introducing beneficial insects like ladybugs can also help control pest populations. Sticky traps in your grow space can also be a great idea. It is really important to keep your grow area clean and free of debris to reduce the likelihood of pest problems. 

Cannabis plant diseases 

cannabis leaves with fungal infection and brown patches

Cannabis plant diseases, such as root rot, powdery mildew, and fusarium, can cause leaf problems. These diseases disrupt the plant's ability to absorb water and nutrients, weakening its overall health and causing the leaves to wilt and droop. 

How to treat diseases on your plant: 

To fix cannabis plant diseases, first identify the specific disease affecting your plant. Remove any affected leaves or parts of the plant to prevent the disease from spreading. Use appropriate fungicides or treatments designed for that specific disease. Ensure your plants have good air circulation and avoid overwatering to help prevent conditions that may lead to disease getting a foothold in the first place.  

FAQs 

What is the most common cause of cannabis leaves drooping? 

The most common cause of cannabis leaves drooping is overwatering. Excess water prevents roots from accessing oxygen, leading to root rot and stressed plants with drooping leaves. 

Why do cannabis leaves bend down? 

Cannabis leaves bend down primarily due to water stress, either from overwatering or underwatering. This stress affects the plant's ability to maintain proper balance of fluids and internal pressure, causing the leaves to wilt and fall. 

Do droopy leaves mean overwatering? 

Droopy leaves can indicate overwatering, but they may also result from underwatering, nutrient deficiencies, or environmental stress. Identifying the specific cause requires examining other signs and the overall care routine of the plant. 

Is it normal for cannabis leaves to droop down at night? 

Yes, it is normal for cannabis leaves to droop down at night. This natural process, known as nyctinasty, occurs as the plant conserves energy and prepares for the next day’s light cycle. 

Understanding why your cannabis leaves are drooping is crucial for maintaining healthy plants. This article covered key causes like overwatering, underwatering, nutrient deficiencies, heat stress, excessive humidity, pests, and diseases, along with practical fixes. Apply this knowledge to keep your plants thriving. Don’t forget to like and share this article!