Hi, Nick...sounds bad, but maybe there is hope before Neem oil. I have only had bad flea beetle infestations on certain plants...eggplant being their favorite. Some years they shoot my young tomatoes full of holes but soon the plants out grow them.. If it were me I would make sure all of my plants were healthy and growing well, get rid of any that attract flea beetles (I think some folks use ameranth as a catch crop) and then I would watch for a natural predator to show up. I think I felt your same frustration here the year THOUSANDS of striped blister beetles moved in...in the end, all of my stomping them and soapy
water and even a little pyrethrum flower spray (I grew them two years and then realized that wasnt the direction I wanted to go) did not make much difference....the shop vac was totally satisfying but not a real solution. They were gone in their own good time and I replanted what I lost.
It does help to know their lifecycle and how may times they hatch over the summer...I thought flea beetles were an early problem and then gone. I am not familiar with neem oil but I would worry you might fix this years problem but throw off your insect balance for next year if it kills everything.
Just my thoughts...not necessarily a solution for you....welcome to Permies!
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