Like most 420 gardeners we've had our struggles with spider mites. It started when we stupidly took a clone after a friend told us it had spider mites. So we had spider mites on that grow and on our 200 houseplants. We bought predator mites time after time. They would beat the spider mites back for a while but never eliminate them. Spider mites are so insidious because it's hard to tell sometimes if a plant has them or not, and whether an infestation is over or ongoing. In a situation with a lot of houseplants, they can never be eliminated.
So we killed off all our houseplants except for one, which was up high and seemed totally clean every time I checked. I have excellent eyesight. Joe calls me sexist for this but I believe there are very few men who are nitpicky enough to find spider mites unless it's already a bad infestation.
After a while with no houseplants, Joe decided to start a new grow. He collaborated with a soil guru to purchase all premium organic soil components and mix them in the ideal way. He transplanted all the baby plants into the mix. Days later? Spider mites.
So even the most careful grower can have them. They’re all over the industry.
What I have learned is that they don’t have to be a death sentence. This time we bought ladybugs and they seem a lot better than predator mites. They’re clearly visible, which is reassuring. They’ve been a lot more effective, faster. And at least with the sources I used, the ladybugs have been more cost effective. I ordered from highsierraladybugs.com and was happy with my purchase. It was cheap, they come alive and you can put some in the tent and keep the rest in the refrigerator for a while. I do feel a little bad that I ordered 750 of these beautiful things and that’s a really excessive amount for such a small indoor grow. They are cute though—they have sex, they fly into the lights, and they see you looking at them. The plants look super clean now, especially the new growth. I’m reassured that we can manage the mites successfully through harvest.
This time we also used a cayenne/garlic/onion infusion as a spray and we turned the fans up high as soon as we spotted the problem, which kept the mites in check until the ladybugs arrived. But I wouldn’t want to rely on just a spray personally, knowing the tenacity of these things.
On the first grow when we had the spider mites, the solution was simply to grow them outside. There were enough natural predators to keep the mites in check and the plants grew well and yielded decently despite continuing to be covered in spider mites.
Spider mites are horrible but if you have some good strategies, namely voracious predators, your plants can survive and yield.