Spider Mites 101 - Please help with my pepper plants!

I'm hoping someone can answer some questions I have about SPIDER MITES, so I can figure out how to get rid of them for good!!

I've had problems with the bugs on my two (indoor) cherry bomb plants this season. One plant got a pretty bad infestation... it reached the point where I could see little webs on the leaves, and mites crawling back and forth on the webs. I treated that plant several times by spraying it with dish soap diluted in water. After about 3 sprays the bugs were gone, but the plant subsequently dropped most of its leaves (not sure if that was from the mites or the treatment). It has since recovered and grown plenty of new leaves and flower buds, so things seem to be going well, but I'm not entirely convinced the bugs are gone. They actually seem to have spread to the other plant as well, and I'm trying to take a less aggressive approach in treating it this time, to avoid leaf loss.

I'm a little mystified by the current situation, actually. Since treating the initial infestation, I haven't seen any more actual insects (crawling, building webs, etc.) on either plant, but I seem to be observing progressive damage to the leaves. The leaves are mostly healthy but when you look closely at them you can see a grainy appearance, with tiny white spots where the leaf tissue appears to be eaten away (see photo).

Is this spider mite damage, or could there be another cause?

The reason I ask is that I don't see any bugs, and yet the spots still seem to be spreading on both plants. I inspect the leaves every day and sometimes I see a few little brown specks on the bottom of the leaves. I'm wondering... are these spider mites, or spider mite droppings, or spider mite eggs, or something else related to spider mites?? I only see a few here and there, and I brush them off with my finger. As I said, I don't see any other sign of bugs... nothing crawling around. The brown specks look very different from the mites I saw originally.

I read a fair amount about spider mite control in other threads. Everyone seems to have their own concoction, including some combination of soap, beer, hydrogen peroxide, neem oil, etc., but I'm wary of causing leaf drop again. I read in one post that water should be enough to get rid them, so I've been blasting the tops and bottoms of the leaves with a spray bottle every day. As I said, I don't see any bugs, but every day there are a few more of these brown specks and (I think) a few more areas of damage.

Can somebody help me figure out what's going on? If there are still spider mites on the plants, wouldn't I be able to see them?? What are the brown specks?

Any insight or advice would be GREATLY appreciated!

Many thanks,

Izumi

Spider mites & aphids- the most terrible terrorists in the world- (at least mine!) I have them every year on my pole beans, no matter how diligent I am. I have a Dramm mister nozzle that I put on my garden hose, and try to aim it at the underside of the leaves, but no way can you hit them all. Tried every concoction-homemade & purchased. They always win. I just pulled up my 2 eggplants and some peppers that were overrun. All I can say is good luck!

Wow, that's discouraging. I only have two small plants, though, and they're indoors, so it seems that I should be able to solve the problem. Since you have so much experience with spider mites, can you answer any of my specific Q's? If the bugs are still on the plant, shouldn't I be able to see them? Are the brown spots related to the mites, or something else?

If you're seeing little brown spots on the underside of the leaves those are the spider mites. There are a couple things that I've found are key to controlling them:
1) whatever treatment method you use, make sure you get the underside of the leaves. That's where they live, so just spraying the tops of the leaves won't get very many of them
2) keep after them. One treatment is almost never enough
3) give the same treatment to any plants sitting near the infested ones, even if they aren't showing signs of problems yet. Chances are there are a few mites on them already and you just haven't seen them yet. If you don't do this, you'll be chasing them through your houseplant collection forever, but if you can get ahead of them by treating the plants that they've just barely gotten to, then you can stop the spread.

I don't typically use chemicals to control them--I only get them on my potted plants, so I tip the pot over and give the undersides of the leaves a really good shower with the hose. I repeat the shower every couple of days for a while and that usually takes care of them. If you want to be extra sure though, you can hit them with insecticidal soap or something after their shower (just make sure you're spraying the undersides of the leaves).

Also, even after you get rid of them, you will often see your leaves continue to look worse. The areas where they've sucked the juices out of the leaves will eventually die and turn brown but that takes time, so even once the mites are gone the plants can look like they're getting worse instead of better.

Oh, thank you so much. YOur post is very informative. I was confused by the brown spots because they didn't seem to be alive, and they looked so different from the bugs I saw crawling on the webs before. I never see the brown things crawling around, they're always just sitting there. Now that I know they are mites, though, I'll be especially vigilant about destroying them.

I'm also glad you mentioned the thing about the leaves continuing to look worse even when the bugs go away. I was wondering why the damage seemed to be spreading as the bug population was diminishing.

I'll continue spraying the leaves vigorously, especially the undersides, until all the brown spots are gone. I'm wondering, though... how far can the mites travel? Should I only worry about plants that were in the immediate vicinity or can the mites spread to plants on the other side of the room? Also, do spider mites prey on cactus plants, or just leafy ones?

Many thanks!

I've only seen them spread to plants that were in close proximity to each other so I'd guess they're probably not on the plants on the other side of the room yet, but definitely keep your eye out for them. Whenever I've had them, I never know how exactly they got there in the first place, but they tend to spread from one plant to the plant next to it. I don't know if they like cactus or not, but it wouldn't hurt to give them a shower too just to be safe.

If I may add another hint- Poor air curculation encourages any insect, especially on those plants inside. Try to use fans or any means of gently moving the air- and have the humidity fairly high will help. Growing veggie plants indoors is a tough job! Good luck.

The pepper plants have been in the windowsill in front of an open window all summer (no, I don't have air conditioning), so I doubt air circulation is a factor. The weather is also quite humid here, so that is probably working in my favor. I'm still spritzing the leaves with water every day, as I mentioned above, so I expect things to continue improving. Keeping my fingers crossed....

I bought these pepper plants as seedlings from a vendor at a farmer's market so I suspect the mites were there when I brought them home. I've never had problems with the bugs on any of my plants before. I'm planning to plant some wild strawberry seeds soon, though, so I'll be sure to keep them far away from the peppers.

Thanks for all your help!

Two days with no new brown spots. Still spritzing.