How to Fix Drooping and Wilting Cannabis Leaves?

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Added 27 May 2023

How many times have you walked into your grow room to find cannabis leaves wilting?

It’s a sick sight, and a nightmare, especially if it’s not because of water problems. 

Drooping and wilting cannabis leaves are often not natural; instead, they are a warning sign of an underlying issue with your plant. 

Typically, cannabis leaves droop or wilt when they experience stress of some kind. If you’re a commercial grower, diagnosing these issues will be a full-time responsibility. That said, even a home grower must be cautious because it may lead to reduced yields if you don’t take care of the problem immediately. 

There are many diseases and deficiencies that can attack your cannabis plant, but the most common ones are drooping and wilting. Whether it is due to improper irrigation, root problems, nutrient problems, or other diseases, it can cause problems later down the lane. 

But what exactly do these symptoms indicate, and how do you fix them? Learn all about drooping and wilting cannabis leaves in this article. 

Drooping vs. Wilting Cannabis Leaves

Drooping vs. Wilting Cannabis Leaves

Drooping and wilting of cannabis leaves are different problems but are closely tied to one another, so we decided to address them together in this article. There are like sick sisters that trouble your plants in coordination. The two problems exist on either end of the spectrum, but how is that? 

Cannabis plants often experience drooping leaves as a symptom of stress or dehydration, which can occur due to several factors like inadequate watering, nutrient deficiencies or lockouts, high temperatures, root issues, diseases, and pests. Drooping leaves typically mean that your cannabis plant is not receiving adequate resources for healthy growth. 

On the other hand, wilting takes place when the leaves lose their rigidity, making them sag. Although insufficient water or nutrients could also cause this, it often suggests a more severe problem with your plant and requires immediate attention. Wilting can indicate root rot, root damage, nutrient toxicity, or other crucial problems hindering the plant’s ability to absorb water and nutrients efficiently. 

It is crucial that you assess the situation, determine the cause of wilting or drooping, and fix the problem as soon as possible. By taking the right steps on time, you can help restore your plant’s vigor and health. Failure to do so can make your plant grow slowly and affect the yield, and in severe cases, such problems can even kill your plant. 

Generally, fixing both wilting and drooping of leaves involves solutions like adjusting the irrigation regime, optimizing nutrient balance, managing environmental conditions (humidity, light, and temperature), eliminating pests, or fixing root problems. 

Fixing Drooping and Wilting Cannabis Leaves

Whether your leaves are drooping or wilting, you need to take quick action to fix the problem. And since both these problems may have common causes, let’s look at some factors that can cause drooping and wilting of leaves and solutions to fix them.

1. Watering Problems — Underwatering or Overwatering 

Watering Problems — Underwatering or Overwatering 

Humans are 70% water, but plants contain even more water at 90%! So, it is no surprise that water plays a crucial role in your plant’s health and growth. Water is used by the plant for various processes like nutrient transportation, nutrient absorption, heat regulation, and much more. 

So, if your plant suffers from watering problems, the above-mentioned processes can be hampered. Due to over- or under-watering, your cannabis plant’s leaves can become sick and wilting or drooping. 

This applies both ways, with overwatering being more common with new growers. Water is good for plants, so it’s natural for new growers to think that watering more will lead to better plant growth. However, that’s not the case — overwatering can be dangerous for your plant. 

Here’s how: your cannabis plant uses oxygen for respiration, where energy is released for the cells to use. In turn, the roots absorb oxygen along with water. When you overwhelm your plant with water, the roots start suffocating, so they can’t absorb enough oxygen properly, which prevents the plant from carrying out respiration and photosynthesis. Plus, too much water can soften the roots and even cause root rot. 

On the other hand, underwatering can also lead to several problems in cannabis plants, including wilting and drooping leaves. Essentially, even a lack of adequate water affects the photosynthetic process and nutrient delivery within the plant, which can stunt your plant’s growth. In some cases, underwatering can disrupt oxygen balance within the plant, which can make your plant spend more of its energy absorbing nutrients via the roots. 

As is evident, both under- and over-watering can lead to wilting and drooping of leaves, and if you fail to address this issue on time, your plant can eventually wither and die. And even if your plant survives, expect a subpar yield from it. 

Solution to Overwatering and Underwatering 

Since both overwatering and underwatering are serious problems, you must fix them immediately. Read on to learn how to fix watering issues with your cannabis plant. 

If you think your plant is suffering from water issues, you need to first take a look at the growing medium, particularly its breathability and drainage. If the growing medium does not drain well, it can retain too much water, which mimics overwatering for the roots — it can suffocate your plant. 

Check the moistness of your growing medium or check the runoff water. For example, if you are growing in soil, the top inch of the soil should be completely dry during watering. And as for the runoff water, at least 20% of the water should run off from the drain holes. 

If the soil dryness/wetness confuses you, you can get a soil sensor. It’s a small device that measures the humidity of the soil and is super cheap. You can get good ones for only $10 to $20 — they are totally worth the money.

On the other hand, if your leaves are drooping, your plant is likely suffering from underwatering. Drooping usually occurs when a plant is trying to conserve its water. So, you need to check the growing medium to ensure it is not too dry. If the medium is too dry, water your plant immediately and rework your watering frequency. Again, a soil sensor can come in handy here. 

2. Nutrient Problems

Nutrient Problems

Watering problems are the most common cause of wilting and drooping leaves in cannabis plants, but if you are sure watering issues are not the cause, the next thing you need to look at is the nutrient balance. 

Sometimes, cannabis plant leaves may droop or wilt due to nutrient problems, primarily nutrient deficiencies or toxicity. These nutrients ensure your plant can carry out various processes, such as photosynthesis and energy generation. If the nutrient balance is not right, the plant may fail to carry out these tasks and can eventually die. 

  • Check the pH Balance and Fix It

Nutrient problems can happen due to several reasons, but the most common one is a wrong pH balance in the root zone. Due to this, the roots may fail to absorb some nutrients, leading to nutrient deficiency, lockout, or toxicity. 

So, the first thing you must do here is to check the pH balance of the root zone. The pH should be between 6 and 7 for soil-based cannabis plants and between 5.5 to 6.5 for hydroponic plants. Cannabis likes slightly acidic conditions. 

Use a pH testing kit or a pH pen to measure the pH of the runoff water. If the pH is beyond the recommended ranges, you can use pH up/down solutions to rebalance it. If the pH of the nutrient solution and runoff water differs, there’s a salt buildup in the growing medium, which can be eliminated by flushing the plant with RO water. 

  • Revise Your Nutrient Solution

If rebalancing the pH does not fix the issue, you must revise your nutrient solution or test your soil. You can use soil testing kits to help you determine the nutrient levels and concentrations in the soil. If the soil is lacking some nutrients, you can either supplement them or replant your cannabis in fresh soil with the right nutrients. It is advisable to always use organic, rich soil. 

Nutrient problems are easier to spot because they showcase themselves on various parts of the plant. Depending on the problem, the leaves will wilt or droop along with the stems turning a different color, the leaves developing chlorosis or rust spots, leaf edges burning, stunted growth, etc. 

Revising your nutrient solution is as easy as double-checking the ratios and following the manufacturer’s recommendations if you use fertilizers or similar store-bought products. 

Remember, your cannabis plant requires various nutrients for healthy growth, especially the macronutrients like nitrogen, phosphorus, and potassium. It is easy to give your plant micronutrients, which are usually already present in rich soil and tap water. However, macronutrients may not always be present. 

So, you need to give your plant adequate macronutrients with the help of fertilizers, supplements, or other organic solutions like compost, bone meal, or kelp. There are a ton of methods to choose from, but you must ensure you give the nutrients in the right ratios. For example, cannabis needs more nitrogen during the vegetative stage. So, account for your plant’s demands during different stages of its growth and fine-tune your nutrient solution accordingly. 

3. Heat Stress

Heat Stress

Extreme heat can affect your plant’s transpiration, which is a process by which plants let out water through their leaves. When the temperatures are too high, the plant tends to lose water at a much faster rate, which can result in dehydration and an imbalance between the rate of water loss and water uptake. This can cause the leaves to lose their rigidity and droop so it can conserve more water. 

Additionally, excessive heat can also impact the proper functioning of the plant’s cells and metabolic processes. For example, it can disrupt the enzymatic activities of the plant and affect its ability to produce energy. Due to a lack of energy, the leaves may wilt or droop. 

Furthermore, excessive heat for a long time can cause heat stress or heat shock in your cannabis plant, which are serious conditions that can damage your plant permanently. They can damage the cellular structure within the plant, which can impact its overall health and eventually kill it. 

To prevent heat-induced drooping or wilting, you must manage the right temperature in your growing area. This may involve practices like providing your plant enough shade from the sun, improving the ventilation system, using reflective coverings to reduce heat absorption, or using fans or air conditioners. 

Aim to maintain the following temperatures in your growing area:

  • Vegetative stage: 70°F to 80°F (21°C to 27°C)
  • Flowering stage: 65°F to 85°F (18°C to 29°C) slightly cooler

4. Wrong Humidity Levels

Wrong Humidity Levels

Even incorrect humidity levels can lead to wilting or drooping leaves in cannabis plants since humidity plays a crucial role in water balance and transpiration. When the humidity is low, the air is dry, which accelerates the evaporation of moisture from the leaves. Here, the plant starts losing water a lot faster than it can absorb from the roots, leading to wilting leaves.

On the other hand, high humidity creates a different set of problems. When the humidity levels are high, the air gets saturated with moisture, which reduces the transpiration rate. This can prevent the plant from releasing enough water into the air, leading to moisture buildup — the leaves can droop and limp because of this. High humidity can also cause mold or fungal infections on your plant, which can cause the leaves to wilt. 

You must maintain optimal humidity levels for your cannabis plant, and this begins by monitoring the humidity levels. If they are not right, you can use various means to increase or decrease humidity in your grow room, like fans, dehumidifiers, humidifiers, ventilation, etc. 

Ideal humidity levels for cannabis are:

  • Vegetative stage: 40% to 70%
  • Flowering stage: 40% to 50%
  • Late flowering stage: 30% to 50%

Remember to decrease the humidity in your grow room at a rate of 5% per week to prevent your plant from experiencing shock or stress. 

5. Lighting Conditions

Lighting Conditions

Like other factors mentioned above, light also plays a major role in the photosynthesis of your plant. However, when talking about drooping or wilting leaves, it is not the presence or absence of light that causes the problem, it is the intensity or quality of light. 

If the light intensity is too low, the leaves may start wilting or drooping. This is because the plant may fail to produce enough energy via photosynthesis to sustain itself, which can slow down several metabolic processes. The result is an energy-depleted plant with wilting and drooping leaves. 

On the other hand, the wrong type of light can also have a serious effect on your plant’s health. For instance, different wavelengths of light contribute to different physiological responses in the plant, and an imbalance of specific light wavelengths can disrupt normal growth patterns. 

This is particularly true for blue light. If your plant fails to receive adequate blue light, it may suffer from leaf wilting or drooping since blue light is crucial for leaf development

Even excessive light can cause wilting or drooping leaves since it can heat up the plant, causing excessive transpiration — just like high temperatures. It can also cause light burns, which often cause leaf wilting. 

To prevent this, you need to use the right quality and intensity of light. Follow these tips to maintain optimal lighting conditions for your cannabis plant:

  • Maintain the right distance between the light source and the plant, as recommended by the manufacturer of the grow lights 
  • Maintain a PPFD of 308 to 617 μmol per day during the vegetative stage and 462 to 926 μmol for 12 hours during the flowering stage
  • Use blue-dominant light during the seedling and vegetative stages and red to far-red light during the flowering stage

These are general tips, but depending on your environment, strain, and grow lights, feel free to adjust the variables for the optimal growth of your plant. 

6. Pests and Diseases

Pests and Diseases

The last major cause for drooping and wilting leaves is pests — such symptoms are typical if your plant is under a pest attack, such as aphids, mites, or caterpillars. These pests can directly damage the leaves, disrupting their normal functions. Here’s more information on how such pests can damage cannabis plants:

  • Some pests feed on soft plant tissues, which can significantly damage plant cells, disrupting the flow of water and nutrients and leading to wilting or drooping leaves. 
  • Other pests pierce the plant tissue and extract the sap, which weakens the affected leaves, reducing their ability to maintain hydration and health, leading to wilting or drooping. 
  • Certain pests, such as caterpillars, can extensively defoliate your cannabis plant by feeding on the leaves. If a significant chunk of the foliage is eaten away, the plant struggles to be healthy. 
  • Lastly, some pests may not directly affect your cannabis plant, but they can carry harmful pathogens and diseases, which can affect your cannabis plant. These diseases can sometimes cause drooping or wilting leaves. 

Therefore, it is crucial to regularly inspect your cannabis plant for any signs of pest infestations, like holes in the leaves, webbing, insects, eggs, etc. If you identify any pests, you need to take appropriate measures to eliminate them. The most common pest control methods include neem oil, organic pesticides, companion plants, and predatory insects. 

Night Drooping in Cannabis Plants

If you notice your cannabis plant’s leaves only drooping or wilting only at night, don’t be worried. That is natural and nothing to worry about. 

Many species of plants, including some cannabis strains, naturally droop their leaves at night. In some cases, this could be because of the plant’s response to cold weather at night. Due to photosensitive cells and an internal circadian rhythm, cannabis is one of over 200 species of plants that is perky during the day and droopy at night. This is known as the nastic movement

Although experts don’t really know why this happens, there are many theories regarding this phenomenon. Some scientists suggest that plants reduce their overall levels of heat loss to keep themselves warm during the night. Other experts suggest that this may occur to let the water roll off the plant at night to keep the leaves dry and pathogen-free. 

Some experts also state that nighttime drooping in plants like cannabis may be a form of self-defense against small plant-eating animals and insects since vertical leaves are harder to access and eat. 

So, if your cannabis plant only droops at night, you need not worry about it. It’s your plant taking a nap. But still, to be safe, you should ensure your plant is not experiencing any environmental stressors during the night, like extremely low temperatures or humidity issues — it largely depends on your specific plant and its growth environment. 

Summary: How to Fix Drooping and Wilting Leaves?

Drooping or wilting leaves are a sign of trouble unless they only occur at night (mostly). So, if your cannabis plant starts drooping or wilting, you need to take the right precautions to restore its health and save the yield. Time is of the essence because some problems can quickly compound and completely compromise your plant. 

As you may have noticed already, drooping and wilting leaves are largely related to water in one way or another, directly or indirectly. So, you need to make sure you are on your toes when it comes to irrigating your cannabis plant. 

If you notice drooping or wilting leaves, start with a process of deduction to fix the problem. Start with watering — ensure your plant is not experiencing water stress, either due to under or over-watering. If that’s not the case, the next most likely reason is nutrient imbalance. Other problems include heat stress, wrong humidity levels, improper lighting, pests, and diseases. 

Lastly, remember to always take care of your plant to prevent this problem from ever occurring. Water your plant well but not too much, and pay attention to the lighting conditions, temperature, and humidity at all times. Ensure your plant gets enough nutrients as per its growth stage. And protect it from pests and other diseases too. Follow these steps, and you won’t have to worry about drooping or wilting leaves on your cannabis plant. 



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