If you do not see any insects, I don't see them, there are only 2 things I can think about: lack of water or too much or... some poison (water or ground).
What material are these containers made of?
Dug out already a plant and had a look at the roots, know what they look like?
Can you keep some, not infected, inside amd/or cover them with a mosquitonet or.. and see what happens?
Since I sprayed with a neem oil/garlic spray and dusted lava rock over the plants, the plants are doing way better.
The musquito net is a great idea... why didn't I think of that myself?? Gonna cover some plants, just in case...
Thanks
You are welcome, ☘💕
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