Spider Mites In Indoor Marijuana Grow Room

Cannabis spider mitesMy marijuana plants were thriving, but then they began showing tiny brown dots on their leaves. The plants seem sad. What’s going on?

When spider mites stick their proboscis in the leaves, they leave tiny brown dots. These creatures are about 1/32-inch long, look like brown/black dots, and can be found on the underside of leaves. If you really watch for a couple minutes, you’ll start to see them moving around. They aren’t technically insects and are related to spiders. They have gigantic families and can reproduce very fast. This allows them to ruin complete marijuana gardens very quickly if they aren’t checked. After the colony has gained in population, the spider mites will start building webs and walking around on them.

To get rid of them, try using pyrethrum at first. Unfortunately, many populations of spider mites are not susceptible to this because it’s been used ad nauseam. If that doesn’t help, try using Cinnamite. It is composed of cinnamon and will kill mites on contact. Many fatty-acid and soap sprays can help a lot as well. Neem oil is also effective.


I have used all the prescribed remedies for spider mites mentioned above. Pyrethrum is fine if you absolutely have to use it;

Neem oil, I can do without. I tried it several times. Not a fan.

I have on thing to say. Diatomaceous Earth will wipe out Spider Mites. Simply purchase a garden duster and load it with *Food Grade Codex DE Later on; Rinse with a hand pump sprayer really well before harvest, and let it dry well before harvest by using fans. Or; You could give it a shower and rub off the leaves. Luke warm water from a rain style shower head will allow you to manipulate the plant and rinse off any residue of DE.