Cannabis flowers can come in many colors, but white typically isn’t one of them. If you notice your plants beginning to turn white, you probably have some questions. Learn why your cannabis might be turning white and what to do about it to preserve your plants and maximize your yield.
What Are the Causes of White Cannabis?
There could be any number of reasons why your cannabis plants are turning white, and figuring out the cause is important to keeping them healthy. Environmental stress is a frequent culprit. Too much light, incorrect temperatures, or improper humidity can bleach your plants, stripping them of their natural color.
Pests and diseases also pose a threat. Spider mites and aphids can leave white patches on leaves and buds, while powdery mildew appears as white, powdery spots. Recognizing these issues early allows growers to take action and protect their crops from further harm.
Identifying Specific Issues
A big part of solving a problem is figuring out what’s causing it. This is no less true when applied to whitening in cannabis plants. To diagnose the reason why your plants are turning white, you’ll need to evaluate them closely and consider all the potential factors that might be at work. These might include:
Environmental Factors
Environmental conditions significantly impact cannabis health and color, and not always in a positive way. High-intensity grow lights can cause "light bleaching," turning bud tops white. Temperature swings and incorrect humidity levels can also stress plants, leading to discoloration.
Position the grow lights at a suitable distance and adjust their intensity to prevent these issues. Keep daytime temperatures between 70-85°F (21-29°C) and humidity levels within 40-60%. Finding the right settings for your plants may take some experimenting, so make changes gradually and observe the results.
Pests and Diseases
Pests and diseases are also likely culprits of plant whitening. Two of the most common pests that attack cannabis—spider mites and aphids—leave discolored and white patches or dots on leaves when they feed on sap. The fungal disease powdery mildew might also be behind things, as the white, powdery fungus coats leaves and buds.
Regular inspections can help you find signs of all of these issues. If you can catch an infection or infestation early, it will be easier to stop it. Look for webbing from spider mites, clusters of tiny aphids, or the characteristic white dusting from powdery mildew. The stakes are high, as neglecting to find and treat these problems could potentially have them spread to your entire crop.
Solutions and Prevention Strategies
Once the cause of whitening is identified, apply appropriate solutions to restore plant health and prevent recurrence. Depending on what caused the whitening, you might need to try:
Adjusting Growing Conditions
Optimizing the growing environment helps prevent whitening and potentially solves other issues your plants might have. Regularly check and adjust light, temperature, and humidity levels throughout your plants’ lifecycle to ensure they’re getting adequate nutrients to thrive.
To help with this, use light meters for proper intensity and thermometers and hygrometers for accurate readings. Consistent monitoring and timely adjustments reduce the environmental stress risks that can cause whitening or other problems.
Pest and Disease Management
If your cannabis plants fall ill or are infested, you’ll need to take steps to manage these problems before they get out of control. If you’re struggling with bugs, you can try introducing beneficial insects like ladybugs or predatory mites to control pests naturally. Alternatively, use organic insecticidal soaps or neem oil to drive them off.
For disease prevention, ensure good air circulation to reduce humidity and prevent fungal growth. Sometimes it’s just as simple as moving plants around and giving them the extra space they need to thrive. If powdery mildew appears, remove affected areas and treat plants with a cannabis-safe fungicide to prevent further growth. Make sure to continue close monitoring for the next several weeks, as even plants that seem cured could still have spores stuck to them.
When to Seek Professional Help
Sometimes, even your best efforts just aren’t enough. If whitening persists or worsens despite everything you’re doing, consider consulting a professional. Experienced growers or horticultural experts have advanced techniques and hard-earned knowledge they can use to help you overcome your whitening issues. Their insight is invaluable, especially in severe cases. In the best-case scenario, they might even be able to save crops that otherwise seem unsalvageable and prevent future problems down the line.
Keep Your Cannabis Healthy and Strong
Seeing your cannabis begin to turn white can be alarming, but in most cases, the issue is fixable. If you can understand why your cannabis is whitening, you can figure out a way to solve the problem. From poor environmental factors to pests to disease, some simple adjustments and proactive measures can bring your cannabis back to full strength in no time. Just keep an eye on your plants to help them maintain their health and maximize their yield.
