When facing marijuana leaf diseases, you’ll find that some can be traced to poor nutrition. That’s usually a fairly easy fix; unfortunately, poor nutrition is not always the reason. If you just cross your fingers and hope it’s not caused by a blight, fungus, or other pathogen, you may be gambling with your entire crop.
It’s best to familiarize yourself with marijuana leaf diseases that are unrelated to plant nutrition. This is especially true if you’re already taking steps to ensure your plants are getting enough nutrition, which of course you should already be doing.
Let’s take a look at four of the most common cannabis diseases unrelated to nutrition that might be affecting your leaves, and ultimately your entire crop.
4 Common Marijuana Leaf Diseases
1. Gray Mold
This is also known as botrytis or bud rot. It is the most prolific of all the fungi that affect cannabis plants. It appears most often in grow areas with moderate to cool temperatures and high humidity, and when plants are too close together. Under these conditions gray mold can quickly become an epidemic and totally destroy your crop in under a week. It’s the most serious threat to cannabis growers throughout North America. Gray mold appears as a grayish white powder on leaves and buds. Sometimes just before it appears it causes small bumps to rise on the tops of leaves.
2. Hemp Canker
This is the second most serious of all fungal diseases that affect marijuana plants. The symptoms first appear as pimple-like lesions on stems and branches of plants. After a short while the pimples turn into lesions that resemble cankers, which then turn discolored and dark. Sometimes leaves and other plant parts become covered in a white, powdery, flour-like substance. Once the canker gets on your plants it’s almost impossible to remove. Entire crops can be destroyed very quickly through fast spreading hemp canker.
3. Downy Mildew
Another fungal destroyer, downy mildew usually appears in areas where there is too much humidity and/or moisture. It also likes dark growing conditions like when plants are too close together. It takes the form of a fuzzy, white substance that looks a bit like cotton. Hence the name downy. Downy mildew produces yellow spots on the top of leaves and white fuzzy areas underneath the leaves.
4. Powdery Mildew
This is another serious disease impacting marijuana plants. It operates much the same as downy mildew and attacks plants in darker growing areas that have a lot of humidity. It primarily assaults the leaves, fruit, and stems of cannabis plants. The main difference between downy and powdery mildew is that the powdery produces white spots on the top of the leaves, as well as on the buds and branches. The downy produces yellow spots on the top of leaves. The appearance of either one of them means serious, possibly crop-destroying consequences for the grower.
Use Preventive Measures to Fight Marijuana Leaf Diseases
To stop marijuana leaf diseases in their tracks, be sure to have plenty of space between plants. This will help prevent spores, blights, and other diseases and pathogens from spreading from one plant to another.
Another important preventive measure is to make sure there is circulating air above and between plants in your grow areas. This will keep excess dampness, a breeding ground for marijuana leaf diseases, to a minimum.
In fact, the purity and quality of the air in your growing environment is crucial since many of the most serious cannabis diseases are airborne. Fungal diseases, spores, blights, molds, and most other diseases are delivered to your plants primarily through the air. For that reason, the best preventive measure of all is the installation of a top-notch air purification system in your growing environment.
Our Technology at Work
The AiroClean420 is an excellent example of such a system. This state-of-the-art device uses technology developed for NASA, originally created to remove pathogens from the air on the space station. Astronauts were trying to grow plants and were plagued by fungal diseases and other airborne pathogens. Once developed for NASA the air purification technology the problem was solved.
That very same technology has now been incorporated into the AiroClean420 in order to help growers rid the air in their grow environment air of all airborne diseases. Air exiting the device is completely free of spores, blight, and all other pathogens.