If you believe you got your spider mites from another marijuana grower, then don’t play games. Get serious and get rid of your mites NOW, before they adapt to your grow room and become unstoppable. Here’s a list of proven spider mite remedies for cannabis plants (from home remedies to organic repellents to serious chemical pesticides)… Before your first treatment…. Control the heat Have lots of air blowing over the plants and top of growing medium Spray spider mites off the plants if you can. Spider mites like the heat and hate a windy environment.
A cool breezy grow space won’t get rid of spider mites, but it makes it harder for them to reproduce so your other control methods are more effective. If it’s possible for you to bring your plants outside or somewhere safe, you might even consider spraying off as many spider mites as you can, to get their numbers down before you start your main treatments. Get a fan blowing over the plants and top of growing medium. Not only do plants grow better with a breeze, great air circulation is great for pest prevention. Spider mites love heat and stagnant, non-moving air. They can’t mate in windy conditions so a strong fan can help keep the infestation from getting worse. A breeze also helps pest treatments go better because fans help spray treatments dry on the plant. Azamax is a time-tested way to rid your grow room of spider mites.
Spray plants 15 minutes before lights out, making sure to drench the foliage under the leaves as well as the top of your soil. Use a fan to blow on your leaves to help things dry. Treat your room more than once, even if you believe the spider mites are gone. You can also add small amounts of Azamax when watering your plants, as it will not hurt your roots but will kill spider mites in the soil. You will need a mister (also called a “One-Hand Pressure Sprayer”) to spray all the leaves evenly. Spinosad Products (safe & organic) – Spinosad products are organic and unlike many other spider mite pesticides, completely harmless to pets, children, and plants . Unlike many insecticides, you can spray spinosad heavily on leaves and roots with basically no negative effects. Spinosad products can be used directly to kill spider mites on contact, but can also be used when watering plants to systematically kill spider mites via the roots. Spinosad can also be effective at fighting caterpillars, thrips, and many other marijuana pests. Can be used both as a topical spray like Azamax and Mighty Wash, and can also be used directly at the roots. Spinosad is an organic insecticide made from the fermentation of a specific soil bacteria ( actinomycete Saccharopolyspora spinosa ) and kills spider mites via ingestion or contact by affecting the insect’s nervous system. Spinosad can be a good choice for organic and outdoor growers, because it is very toxic to spider mites, but is less toxic to many beneficial arthropods. Note: Most spinosad products are effective for only about 24 hours after being mixed with water, so only mix as much as you will need per application. You will need a mister (also called a “One-Hand Pressure Sprayer”) to spray all the leaves evenly. Essentria IC3 Insecticide is a mix of various horticultural oils which are organic and safe for humans. It is often marketed as a “bed bug killer” but it can be effective against many bugs, including spider mties, when the plants are treated regularly. Unfortunately, it only stays effective on the plant for about 8-12 hours so you will want to either apply this daily or (better idea) combine with other options. You will need a mister (also called a “One-Hand Pressure Sprayer”) to spray all the leaves evenly. Fatty acid salts or insecticidal soaps weaken the outer shell of spider mites but are safe for humans and don’t leave much of a residue. With soaps, coverage is very important as it does not stay on your plant for long, so follow-up applications may be necessary. Although this is considered safe, avoid getting any on your buds so it doesn’t affect the taste/smell! This spray is hard on spider mites, but the main ingredient Pyrethrum can also be hard on plants, especially in tight spaces without much ventilation, so keep it as a last resort if possible. Use with extreme care around humans as the ingredients can be toxic. Never use Pyrethrum-based products on your plants while your grow lights are on as it can burn your plants. Avoid using Pyrethrum products on young or sensitive plants as they can get burned even when the lights are left off. Do cover your grow lights and vents when bombing your plants with Pyrethrum and make sure you give the area at least 24 hours to air out before you try to breathe the air. This spray can work well for a couple of plants, but you’ll want a Pyrethrum fogger if you have a lot of plants to treat.
Outdoors, Pyrethrum can kill beneficial insects too, so keep that in mind if you’re using natural predators to control pests (like ladybugs).
All that being said, this spray will work to get rid of most spider mites, and it kills them on contact.