Bordeaux is good. I have used it in the past.
I trim off any leaves touching the ground. That helps a lot.
I like to use liquid foliar feeds. Just a mixture of seaweed, molasses, apple cider vinegar, and fish emulsion.
I also pour out out of date milk around the base and all of my used tea/coffee grounds make a good fertilizer.
And epsom salt in low doses.
Just saw some of my poblano transplants (low to the ground and tiny, had some bugs nibbling on the leaves.
Had to break out my Castille soap solution to “nip it in the bud”