Most indoor cannabis growers use fans to blow air around within the grow area. This creates a nice breezy environment that cannabis plants love. But sometimes there can be too much breeze!
Be Careful! Too Much Wind Causes Clawed Leaves and Sometimes Spots
When there’s too much breeze, the affected marijuana leaves will start getting “wind-burned.”
Wind-burned leaves are often curved under and form “claws.” They can look like they’re droopy from overwatering, underwatering, or possible a nitrogen toxicity, but you know you’ve got wind-burn when the leaves in front of the fan are clawing, and leaves further away from the fan look fine.
Just for reference, here’s what too much wind/fan looks like!
Too Much Fan!
Sometimes too high levels of wind can cause other unusual problems on the affected leaves, such as brown or bronze spots that almost look like burn marks. These are the result of the leaf not being able to fulfill all its normal processes.
A closeup of those wind burn leaf spots – not bugs, not a nutrient deficiency!
Ideally you’d like a nice breeze surrounding the main canopy, which means you want air blowing above and under the plants.
All the leaves should be gently rustling in the best-case scenario, but should never be waving around.
Don’t point a strong fan directly at a plant, because too much wind can start to damage the leaves and stems. Sometimes if you have a small space it’s better to point the fan at the wall than directly at the plants.
After placing fans, check around the grow area to make sure that all parts get a slight breeze. If you feel stagnant air or a lack or breeze, you may want to adjust your fans.
Small oscillating fans are great for the grow space since they’re cheap and can be used to provide a nice gentle breeze to a relatively wide area without blowing on any one part too long.
If you cannot get rid of the clawing symptoms from marijuana wind burn, please consult our 7-Step Remedy to 99% of Cannabis Growing Problems for more help!
- Bronze or brown patches
- Brown or slimy roots
- Brown or yellow leaf tips/edges
- Buds dying
- Buds look odd
- Bugs are visible
- Curling or clawing leaves
- Dark leaves
- Drooping plant
- Holes in leaves
- Mold or powder
- Pink or purple on leaves
- Red stems
- Shiny or smooth leaves
- Spots or markings
- Twisted growth
- Wilting leaves
- Yellow between leaf veins
- Yellow leaves
This page is part of our Plant Doctor series. You can use our tool to filter by symptom and help diagnose your plant.
Exposure to too much breeze from the fan can affect the cannabis leaves to start to curl and "claw." Learn about wind burn and how to prevent it.