Spider mites are tiny little mites that are closely related to spiders and have a uniform bodies and strong mouths that can pierce the outer skin of leaves so that the mite can suck out the sap from them.
Spider mites are probably the most common pests that you can get in your indoor autoflower grow operation. They are a pain to combat and are almost impossible to completely eradicate.
Spidermites are very small and can be either black, red or translucent, and they are usually introduced into an indoor garden either by transferring them on clothes from another garden or with a new plant that is brought in from the outside or from another grow operation.
Even a single spider mite egg can start a full-fledged infestation because these little pests are ready to reproduce in about 3 days. They quickly spread by laying new eggs and can completely ruin your garden in a matter of few weeks.
The dangers of a spider mite infestation on your autoflower plants
Spider mites are dangerous because they suck out the sap of your plants leaves and can easily transfer from one plant to the whole garden.
While, if the spider mite infestation is left untreated, the spider mites will start to produce webbing that will completely envelop leaves and buds, making them unusable.
How to prevent spider mites in autoflowering cannabis
Spider mites thrive in warm, low humidity environments, and the best prevention techniques is to keep the temperature below 80 degrees F (26 C) and keep the humidity level above 40%.
But despite that, you also need to be super careful if you get a new plant from a friend or move an outdoor plant inside with the rest of your garden. Autoflowers are great because you always need to start them from seed, so there are no chances of getting mites from bringing in clones, but some growers still like to trade plants and move them indoors if the weather gets too cold outdoors.
Signs of a spider mite infestation
The first signs of a spider mite infestation are small, white spots on your plant leaves that are followed by those same leaves turning yellow and getting enveloped by a delicate spider web.
If you are seeing some discoloration on your leaves, then you should check the undersides, as spider mites usually live underneath the leave, where it is easier to pierce that leaf skin.
If you see red or black tiny moving specs on your plants, then your autoflowers have a spider mite infestation, and you need to immediately start combating these pests while they haven’t completely ruined your whole crop.
How to kill spider mites on autoflowers?
The first line of defense is to completely soak your plant in pure water with a strong sprayer. Be sure to direct that water mist to the undersides of leaves to knock out those adult mites as well as their eggs, which hatch every 3 days.
When you have a spider mite problem, it is really hard to completely get rid of it. But with constant application of water once or twice a day you can stay ahead of them and at least harvest a decent crop before completely sanitizing your grow room for the next grow.
You can also use neem oil or the same insecticidal soap solution, but they won’t completely kill all those mites, and even with strong chemical insecticides it is hard to completely eradicate these pests.
If you recognize the problem in the late stages of the infestation, when those mites have already created webbing around your plants, then in most cases it is easier to simply chop those plants down and start over with a clean room and brand new seeds.
This is a text from the chapter in my ebook “Autoflower Growing: Growing cannabis has never been easier“