Plant diseases are a major headache in any grow operation and Cannabis has no shortage of diseases. So for today’s disease profile we’re going to discuss Bud Rot, a disease you may find yourself dealing with in your grow.

Quick Look

1. Common Name: Bud Rot or Gray Mold
2. Scientific Name: Botrytis cinerea
3. Symptoms: Fuzzy gray mold
4. Caused by: Fungus
5. Timing: Year round

Writer’s Note: Bud rot should never be smoked or otherwise ingested. It is never safe, and doing so can cause serious complications for patients with lung ailments and/or compromised immune systems.

What is “bud rot”?

Bud Rot is a fungal infection that affects the buds of cannabis plants. It starts growing on the stem inside the bud and spreads outward (much like apple rot), and as a result it can be very hard to detect. As bud rot grows, it destroys the surrounding bud from the inside out, eventually producing spores to transmit to nearby buds, and turning what remains into a slimy mush in the process. Like other fungi, bud rot thrives in high humidity environments. However, unlike other fungal ailments, bud rot likes relatively cool temperatures.

What to look for

Bud rot appears as a fuzzy brown-gray mold on stems and buds. An often overlooked symptom is the growth of black seed-like structures that grow from the infected buds. These are best observed with a handheld microscope or jeweler’s loupe.

How to Treat/Prevent Bud Rot

There are no approved fungicides available for dealing with bud rot, so prevention is important. The best way to prevent it from starting is to control the humidity and temperature of your grow. Air flow is also important to keep bud rot from settling in. If you discover bud rot in your grow operation, you should remove the affected bud(s), being careful not to let the affected buds come into contact with other buds. You may have to remove an entire plant if the bud rot is widespread. Do not shake or otherwise cause the infected portions to vibrate -- doing so may release spores.

Editor’s Note: Bud rot can also be carried by insect pests! All normal prevention methods for insect pests can help as well.

So now you know a bit about bud rot and what you can do to prevent it from ruining your grow. Have additional questions about bud rot? You should join our forum where you can post pics and ask our expert community about this topic or any other!

Happy Growing!