Pay attention that growing marijuana may be subject to special restrictions and regulation in your country or state. Please contact your attorney to obtain advice before cultivating cannabis.
Disclaimer
Pay attention that growing marijuana may be subject to special restrictions and regulation in your country or state. Please contact your attorney to obtain advice before cultivating cannabis.
No matter how well you take care of your cannabis plants, there is always a chance that they will become sluggish or yellow. To prevent yellowing or cure the plant after it has already turned yellow, you need to be able to recognize the cause and know the algorithm of action, if it has already happened.
Why Cannabis Leaves Turn Yellow
The yellowing of leaves significantly impairs the process of photosynthesis in the plant, which prevents its normal growth and development. This is due to the degradation of the green pigment chlorophyll, which is supposed to absorb sunlight and produce energy for the plant, and the dominance of yellow or orange chloroplasts. What are the possible causes of this?
Watering Problems
This problem is the most common cause of yellowing cannabis leaves. This can happen both due to excessive watering of the plant and due to insufficient.
Excessive Watering. If the plant receives too much water, the latter will not allow oxygen to the roots. Excessive watering will make your marijuana leaves look full and swollen. The reason may also be a poor drainage system, if for example there are no drain holes in the pot, which remove excess water, or they are not enough. It is also possible if a small cannabis plant is planted in a large pot, which causes it to receive too much moisture. To prevent this from happening, or to correct this problem, you need to change your watering system, such as watering less or less water. The main thing is not to allow cannabis to turn completely yellow, so you need to take care of your plants.
Underwatering. The symptom of underwatering is that the leaves look thin and slack. Too many cannabis plants may grow in the pot, so they do not get enough water each. It is also possible if you left and missed the watering day. In such cases, you need to adjust the amount of water that cannabis receives each time so that it was enough for normal plant life.
Nutrient Deficiencies
In case of nitrogen deficiency, the whole plant becomes pale, and some leaves may turn yellow (with excessive amounts of nitrogen the leaves become darker). Nitrogen is needed by the plant for growth, it is especially important for new leaves. If there is not enough nitrogen, the upper leaves may begin to absorb nitrogen from the lower leaves. As a result, the leaves lose the nitrogen they need and begin to turn yellow and fade. To prevent this, the plant should be given sufficient nutrients, including nitrogen. If you have corrected your nitrogen intake after this problem, but the symptoms have not disappeared, it is most likely that the yellowing is caused by some other factor.
pH Imbalance
This situation is possible with the wrong level of acidity of the water you pour cannabis. The normal level is usually around 7.0. If the pH level is low, the plant will not be able to consume enough nutrients from the soil, as they will be taken away and neutralized by water. Therefore, it is important to maintain an appropriate level of water acidity so that the leaves are healthy.
Lighting Issues
It is well known that lighting, as well as watering, is one of the key factors in the growth and development of any plant. Lighting problems can cause cannabis leaves to turn yellow.
Burn Leaves. Excessive exposure of the plant to light or too close to a light source can cause this. This reason is quite easy to detect because it turns yellow just the upper leaves, which are closest to the lamp. To solve this problem is simple: just move the lamp away from the plant, as well as correct the lighting mode if the plant is too long in the light.
Lack of Lighting. If your cannabis plant does not get enough light, the lower leaves turn yellow and become flabby because they receive less light. The solution is similar: to correct the mode of light supply to the plant.
Temperature Problems
Temperature problems can occur in two extremes: overheating the plant or hypothermia. This is possible in case of deviation from the ideal temperature for growing - between 18°C and 28°C (70-80°F).
Heat Stress. Temperatures above 28°C (80°F) slow down the process of photosynthesis, which can cause the leaves to turn yellow. Therefore, it is necessary to take several preventive measures: to ensure and control sufficient air circulation in the room, to create temporary shade (in the case of growing outdoors), to prevent overheating from the lamp.
Cold Shock. At too low a temperature, the plant withers and turns yellow (it can even turn purple). Therefore, growers need to make sure that cannabis plants do not overcool, especially if you grow them in the basement or outdoors.
Pests
General weakness, yellowing, and most importantly - the presence of spots and traces of insect bites - the main signs that the plant suffers from pests. To prevent this, you need to stop the negative effects of the environment: limit access to cannabis for pets, do not overflow the plant, always wash your hands and cover your hair. Most often, the plant is affected by fungal flies, which feed on the root of the plant, if it is in a humid environment. That is why you should follow the correct watering of the plant and do not overwater cannabis. To get rid of these and other pests, you need to apply insecticides to the plant. However, since it is quite difficult to remove insects, it is better to prevent their appearance on the plant with the help of these preventive measures.
How to Determine The Cause of Yellowing?
The easiest way is to determine the cause of which leaves have turned yellow. If lower - the problem is most likely a lack of nutrients or insufficient lighting. If the top - this is most likely a burn.
However, it is much easier to prevent the yellowing of the plant by proper watering, lighting, and nutrients.
Cases When Yellow Leaves Are Not a Problem
There are situations when the yellowing of the leaves is natural and does not require intervention. For instance, the yellowing of leaves is characteristic of plants at the final stage of flowering. This is also possible with the wrong lighting mode, but such leaves can simply be removed and the lighting corrected so that other leaves do not turn yellow.
How to Fix Yellow Leaves on Plants?
We know that a plant that suddenly loses its signature green can be upsetting to look at, but try not to worry too much. If you follow our tips closely, you can turn the situation around.
- Step 1. Identify the problem. We know that the yellow leaves might make you think something went terribly wrong with your plant. Still, the root of the issue can actually be a completely harmless natural aging process after flowering (senescence). However, if you’re unlucky, you will have to deal with chlorosis, the loss of chlorophyll, an essential fuel for photosynthesis. Interveinal chlorosis is especially common in new growth.
- Step 2. Identify the cause. Do you water your cannabis correctly? Once the soil dries, the plant needs a sip again. Both under- and overwatering can cause the yellowing of the leaves and even trigger root rot. Another common cause can be nutrient deficiency or nitrogen burn (under- or overfertilization). Alternatively, the yellowing can also result from incorrect pH, lighting, and temperature issues (temperatures below 50°F/10°C can be dangerous). Finally, there’s always a chance there can be a fungal disease or pests causing your greenie some trouble.
- Step 3. Work on a particular solution. If your leaves are yellow due to watering issues, find a way to establish a proper watering schedule immediately. You can lift a pot and remember how it feels when it’s full of water. This way, you can always tell if your plant is thirsty. If the issue is nutrient-related, either abstain from feeding your green pet and run water through the soil to cleanse it or slowly begin feeding it with organic seaweed fertilizer. For incorrect pH, you should consider repotting your plant to a different soil or using a balanced fertilizer or a pH pen. Adjust the temperature to a comfortable 68-77°F (20-25°C), and move your plants away from heaters and ACs. Move the plant from intense light or enhance it, depending on the issue. In case you find any pests, neem oil should be applied.
- Step 4. Cut the yellow leaves. Unless your plant is very young, it's completely fine to trim your plant. By doing so, you can improve its appearance and help it focus the energy on healthy growth.
Done! If you followed all four steps, you can now wave the yellowing goodbye and relax. Not so scary of a problem after all, isn't it?
FAQ
Should We Cut Off Yellowing Marijuana Leaves?
If your plant is mature, it is acceptable to cut off the leaf that has turned yellow and wrinkled. The plant can use the energy to distribute to healthier leaves, and you can help it save on this energy by removing the dead weight.
Can Yellow Leaves Turn Green Again?
Generally, once the leaf turns yellow (especially if it's also crispy), it is unlikely to restore its original green color. However, new leaves can always sprout and make your bush pretty again!
Why Are Marijuana Leaves Turning Yellow During Flowering?
If your cannabis is yellowing before the blooming period, it means that the natural process called senescence is taking place. This process usually occurs at the end of the growing season.
Whatever the cause of the leaf yellowing, it is probably reversible with proper care and treatment, so don’t panic! Remember, growing plants requires a lot of patience and takes some time, but it always (and we mean always) pays off in the end.
