Spider mites are a very common pest among indoor houseplants. They damage plants, like cactuses, by consuming juices from the inside of the plant. Even though cactuses generally look pretty tough, with their thick leaves and bases and thorny exteriors, they are susceptible to infection by spider mites. Treating cactus spider mites in a timely manner is key to keeping your cactus healthy and alive.
What is a spider mite?
“Spider mite” is a broad term used for members of the Tetranychidae family, which encompasses 1,200 known species. Spider mites, like spiders themselves, are arachnids that live on the underside of plant leaves and spin protective silk webs. Spider mites are not spiders, but their webs resemble spiderwebs, which is how spider mites get their name.
Spider mites look like small black, brown, or orange mites on the underside of plant leaves. They are very small and may look like tiny dots. A spider mite infection is usually accompanied by web-like silk that has been spun around infected leaves.
Treating spider mites on a cactus
Treating cactus spider mites is a pretty straightforward process that is difficult to mess up. There are two options, a DIY miticide or a store-bought miticide. For the DIY miticide, simply mix a teaspoon of dish soap in with a quart of water. Poor the mixture into a spray bottle and spray the parts of your cactus infected with cactus spider mites. Be very careful not to spray the soil, as soapy water may harm the plant if introduced to the soil. A safe way to do this is to lean the cactus over your sink and gently spray just a little bit of the DIY mixture onto the cactus.
You can also purchase a miticide from any garden center or nursery. To use a miticide, consult the instructions on the package and follow them carefully.
Preventing future cactus spider mites
The best way to treat cactus spider mites is to prevent them from getting a foothold in the first place. But it can be difficult to do. Still, controlling and preventing spider mites is something any gardener can do.
Quarantine new houseplants
Any time you bring home a new houseplant or cutting, be careful to quarantine it for a few weeks. Quarantining will help you determine if the plant is infected. Spider mites will reproduce very rapidly, so even if there are only a couple of mites on the plant, after a few weeks, it will become very apparent. Quarantining new houseplants can save you a lot of work and heartbreak later on.
Keep a close eye on leaf health
If you’ve brought in new houseplants recently or have had repeated problems with spider mites, inspect your plants weekly for mites. Keep a close eye on leaf health. Leaves that are impacted will look unhealthy and have spider mite webbing on them, particularly on the underside.
When in doubt, treat plants periodically
Finally, if you have been experiencing frequent difficulties with spider mites, purchase a miticide and treat your plants periodically. They say an ounce of prevention is worth a pound of the cure, and in the case of spider mites, it’s worthwhile to focus hard on control and prevention, especially if you’ve had past difficulties with spider mites.