08/01/2026
Your cucumber is inadequate. 🤏🏼🥒
I said it, and I mean it.
You may have seen people recommending the use of cucumbers for combating mite issues. I think people may be confused about this, so I figured I would clarify a bit. Cucumber does not kill or hurt mites in any way. The moisture in the cucumber is actually just attracting the mites so they can easily be removed manually from the setup. That's why the recommendations usually say to replace the cucumber often, as taking the old cucumber out is literally removing the mites that climbed onto it.
You can actually replicate this with a simple deli cup full of water. You can put a small deli cup of water in a mealworm bin or any other mite infested scenario and they will swarm that cup like it's free food on a college campus. If you add a drop of dish soap to the water, it even turns the deli cup into something of a mite death trap because the soap messes with the water surface tension and many of the mites sink to the bottom and drown. Kinda like how fruit fly traps that call for soapy water work. When I first experienced a mite issue I used deli cups of water paired with climbing barrier to catch and kill teaspoons worth of mites per deli cup 🤯. This is part of the reason I don't keep humid environment feeders in my spider room anymore, if at all. It was the discoid roaches 😅.
I have seen people post entire guides on mite eradication and combat techniques. The helpful intent is great, but I feel like many of the solutions offered are subpar, and distract from the true issue and relevant solution (I'm getting there). I understand where people are coming from though. Mites are gross, no one wants them, and when you are dealing with them it's a LOT to handle if you are following salad methodology or wiping down all the surfaces constantly. I've been there. I struggled against the mites that were breeding (unbeknownst to me) in my discoid colony. I fought them for months after realizing what was happening. I tried cucumber, I tried pea powder, I tried water traps, I even made battle lines of diatomaceous earth around shelving units. I tried everything and more you could find in most of the guides, and when I finally figured out what worked I felt a bit foolish.
I'm going to share a secret. There is a very simple way to completely eliminate most mite issues, and it does not involve anything as distasteful as salad ingredients. The key is one variable, humidity. Humidity is the main issue that causes mites (usually 70%+), but it's also the solution. Humidity close to or under 50% will cause most mites, like grain mites, to desiccate (death by drying out) within 2 weeks. They need extremely wet conditions to thrive and breed. This is THE MOST EFFECTIVE thing you can do to deal with a mite issue.
How does it relate to keeping jumping spiders?
Many people have read a Google result or AI generated guide about jumpers and saw a recommended humidity of 60-80%. For the most popular species in the hobby, this is not true at all. Jumpers rely much more on internal hydration for successful molts than they do humidity. As I write this my spider room is reading between 41-46%. Too much humidity all the time can actually cause a jumper's exoskeleton to dull and soften, and they end up passing away. Humidity in an enclosure should fluctuate between spritzing. It may be as high as 75-80% after a spritz but reach back into the 40s before the next spritz. This is normal and fine. So if you are having a mite issue, allow the enclosure to dry out a bit more between spritzing. You can also move the jumper to a temporary bare bones enclosure or cup for the 2 weeks while the original sits fully open and dries out. This would be ideal for jumper species that truly need the higher humidity, move them to a clean enclosure in a new location while the old one dries out. Be aware that the mites will abandon ship as soon as the enclosure starts to get dry. I highly recommend using a ring of DE around the enclosure to prevent them from spreading. You can use newspaper under the enclosure/DE to avoid things making a mess.
Also adding this tiny section to mention mites that are ATTACHED to a spider will abandon ship in dryer environments as well. Hydrate the spider with a good feeder and let them experience a period of dryness and the mites don't stay on for long. Many mites are only hitching a ride, and very few species are actually going to be feeding on the spider.
What if your whole room is humid? This can definitely be an obstacle. The tiny affordable dehumidifiers you find online are 💩, and the good ones can be spensive. Your best bet is to run your AC extra to drop the humidity. AC units pull humidity out of the air when cooling. You could also potentially find a high quality dehumidifier for rent. My house was built in the 70s and we are in Florida, and our indoor humidity still naturally hovers around 50%. Maintaining a dryer environment than the mites require should be very feasible for most people.
What about fruit fly cultures? First of all, if you aren't raising slings (like the legitimate babies), you do not need a fruit fly culture. Fruit flies are not a suitable feeder option for Phidippus species past the first few instars. Feeding fruit flies to juvenile or older Phidippus species can be entertaining, but the flies offer no benefit to the jumpers at that age and the flies lack proper hydration the jumpers need to molt successfully. But if you ARE raising slings and you DO need fruit flies, it's a great idea to keep them contained and separated with a bowl of DE. If your cultures are coming from an outside source there is a very good chance they will contain some mites, and this is normal and not usually a big issue. If you are making your own cultures you can freeze your dry media to eliminate potential mites and eggs. The DE bowls are a great method though and have really helped me keep my own cultures clean since implementing them.
If you are currently thinking "MITES?! I didn't know mites were a possible issue!", please remain calm. If you are not keeping your enclosures too wet, and not dealing with fruit flies or other humid feeders, the chances of you ever experiencing a mite issue are almost zero.
This started as a short spur of the moment post and became a bit of a long winded Ted talk. Hopefully it's helpful. I would greatly appreciate this post being shared. Feel free to copy the link and post it if you see someone in a group asking about mites. If you find this information helpful and are not following my page, please consider doing so. I try to be transparent about jumping spider topics and care, but most of my time is spent producing captive bréd spoods.
