One of my micro RL container plants has something other than the usual Septoria/Early Blight on its leaves. They started off with yellow spots all over the plant and I finally got around to examining it today.

This looks as if spider mites have chewed the underneath of the leaves, except there is no evidence. No bodies, cast-offs or webs. However, the leaves attract debris which clings to the under side of the leaves and is obviously from the peat-based planting mix, yet the leaves are at least a foot above the soil! I examined several of the leaves with a magnifying glass, but can't really post pictures of close-ups.

Does anyone have any clue what this can be?

Linda

I can only mention other tiny pests, thrips for example. Mites... not 'spidermites' necessarily there are others. Spruce mites for example. Will infest all kinds of non spruce vegetation afaik.
Tiny pests drive me nuts... what is it? where is it?

Thanks Bower. I decided that they were mites (if not spider mites) that perhaps were not in residence. I found a "natural" spray mix of vinegar, baking soda, water and a drop or two of Dawn. I sprayed the plant well, and wish I hadn't as it's now looking very sad .

Linda

Aww. Our whole garden is looking sad like that, day three of a drizzly foggy cold wave. Bet your plant will be fine when the warm sun dries it off. Some pests however... so hard to get rid of... I hardly know what they are, it seems I am foiled.

Thanks for the sympathetic note. I may have killed the plant, so thank goodness it's only one. I'm sorry that you are dealing with pests .

Linda

Yeah there are a few pests I can't get a handle on. Spruce mites? Could be. Some small larches around the garden are badly affected... I'm wishing I had cut them down in the spring. There's something on the oregano - this is a problem going on now for years. Leaves covered in speckles. Doesn't seem to bother the plants, but then it spreads to other things. I've been waiting for the right predator to do its thing but it's not happening. Cutting back on oregano (which there is way too much of anyway) but then I feel bad for the bumblebees, so I can't be as ruthless as I should. I see it's getting on the potato leaves as well! Overall everything is okay in spite of a few pests.
Sorry about your tomato plant.

Bummer about those mites Bower! If you decide to get rid of the oregano and need flowers for the bumblebees, they LOVE blue flowers. In my garden, they really like Nepeta, Agastache, and Lamb's Ears, as well as Borage and, as an added bonus, I have Painted Lady caterpillars in the Borage this year .

Linda

I concur that thrip damage does look like spider mite damage (sans the webs).

Don't forget that there are different kinds of spider mites, too, and they can be pretty different. The kind in my area are hardly ever big enough to be visible, even with close inspection, but they make webs all over when the infestations are heavy. With a light infestation, I don't see a lot of webs, though (usually just strings of webs that I think they travel on). They mostly go for indoor plants, outdoor watermelon and outdoor first-year ground cherries in my area, but they're everywhere.

When there's enough water for predatory insects to thrive, I think that's when the populations can go down. Same for variegated grape leafhoppers (which also make damage that looks similar to spider mite damage; I've seen them on grapes, alpine strawberries, and some herbs in the mint family, but not on tomatoes). I imagine other kinds of leafhoppers might cause similar damage on tomatoes; I know leafhoppers can spread the curlytop virus to tomatoes, anyway. I never found out whether our apple tree damage was from spider mites, thrips, or leafhoppers (but we don't have apple trees anymore). They were heavily damaged every year for a number of years. It's better to grow peaches, nectarines, and plums, when the weather is so hot and dry. Pears used to be a good option, until ours got fireblight. Apricots would be great if the frosts didn't kill the blossoms so much.