sick peppers

[wally mcgee]

I have always had a hard time growing peppers in my garden in Iowa..zone 5a. Everything else seems to flourish in my soil, but peppers never seem to do very well. I am attaching several pictures of them; 2 sick looking plants in the same bed, and a little bit better looking one in another bed.

I usually use fish emulsion on most of my plants, but these peppers hate it.
The only difference between the two garden beds is the ph of the better looking pepper bed was 6.5 and from the other bed, 7.5. So says my newly bought cheap ph tester. Could that be it? If so how do I correct it.?

All the surrounding plants: broccoli, cabbage, zucchini , and Cherokee Purple tomatoes all look very healthy.

You can see that the pepper on the right looks good compared to the one on the left in the other bed. I should mention that in the bed with the sick peppers are some ground cherries I'm trying this year, and they don't look so hot either.

I'm at a loss.

Any thoughts would be appreciated.