Not quite spider, not quite mites, these bugs are the worst of two worlds. They are very, very small, and if you are not looking for them on your succulents, you could easily be overlooking them. Spider mites love succulents because they harbor a high concentration of sweet sap that they like to suck out. If your cactus is infected, you will see yellow and rust-colored spots on the stem, which can cause the plant to become weak and infected with other problems.
It is important to know that spider mites are not typical bugs like most pests. Instead, they are a type of arachnid, like spiders, so regular bug sprays and pesticides for bugs will not kill them. In fact, those pesticides may be killing off the good insects that feed on spider mites. Therefore, you will need to deal with spider mites in a more specific way.
How to Control
If you see white webs on your plant, clean them off as soon as possible. If you see the spider mites themselves, brush or pick them off and dispose of them away from the plant. You may even want to remove the entire plant to prevent the mites from getting onto your other plants.
If your spider mite problem is really bad, you could try a natural "systemic insecticide." You either add mix when you water your plants or unpot and wash them in the insecticide solution. After using the treatment for a couple of weeks, the plants will absorb the poison into their system so that when bugs suck out the plant sap, they will be poisoned. Use these systemic insecticides very sparingly because they are pretty potent and may damage your plants if you use too much.
If your succulents grow outdoors, use a sprayer that has a strong jet stream to blast the mites off.
There are predatory mites that will eat the bad spider mites that are dining on your plants. But, of course, this solution is better for outdoor plants because you will not want any bugs in your house.
- Succupedia: Browse succulents by Scientific Name, Common Name, Genus, Family, USDA Hardiness Zone, Origin, or cacti by Genus