Hard to tell from your picture, as you can barely see them, but they might be black aphids and, if elongated, they might be thrips. Can you look more closely and give a description? Aphids are pretty common on alliums. Most any insecticide will do the trick, and sprayed soapy water will probably work as well. One tablespoon per gallon. Aphids suck plant juices, and your plants don't appear damaged, so no need to replace yet. Of course, if you replace the plants, the bugs will just be back. A little surprising because you're already spraying them, and they don't seem to be going away. Spray more.

They look like aphids to me too. I'd just wipe them off with a wet cloth.

hard to tell what kind of pests those are based on the photo, but I would recommend to let it be removed by a professional pest control company, because it looks like they are with many and can do a lot of harm to your plants etc. most people don't have the equipment to remove them the right way.

Neem oil is fairly toxic and many neem products aren't the natural oil, but the pesticide extracted from the tree. I'd read carefully and do some research before eating any produce sprayed with neem oil, particularly something that can't be scrubbed like scallions.

I'd inspect your other plants, but if they aren't infected, the bugs are probably onion thrips. In a small planting, wiping them away daily may work.

Fair point about neem oil, though azadirachtin is considered just an irritant in small quantities. Organic pesticides are somehow always assumed to be benign because, um, well, they're organic! Of course there are many plants that are deadly poisons, and they too are completely organic.

Very hard to tell much from the photo - they look a lot like chia seeds, even when enlarged 😄

Do they fly, or just crawl, and if crawling, are they fast or slow? Thrips are usually thin-bodied and move rather quickly, compared to aphids, which move very slowly, and fungus gnats fly around when disturbed.

None of those pests are harmful to people, and the onions shouldn't need to be replaced.

I agree about simply wiping or washing them off. I also might dust it all with some diatomaceous earth (DE), which needs to be dry to be effective.

Perhaps letting the pot dry out a bit might help as well. Onions are bulbs, so they can withstand dry soil for some time.

Wondering whether Adam Moors is a real human being...?

There are a few which are clearly identifiable as aphids. eg top right. Fat body, angled legs.

I think that's right. You can blow up the image some. They're clearly not long like thrips. Fungus gnats would have prominent wings. Still a bit perplexed why soapy water and neem haven't gotten rid of them, though they have to actually eat the neem, and if the soapy water washes the neem off, that won't happen. Might be smart to spray the soil surface with soapy water as well, since they can breed in the soil.

Thanks very much for all the replies. I'll try a combo of what y'all recommend (minus the pest control company, of course ;-) BTW, while I suppose there are various types of neem products - some of which may be more authentice than others - this is the one I've been using...

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