Johannian said: The last three years have really just been flops,
Some of it can be variety interacting with climate. I'm 6a but a heavily influenced by the Great Lakes mitigating both winter lows and summer highs 6a. A good chunk of my growing season still has night time average temps <60F which pepper plants don't like. Shorter day to maturity selections might help. Varieties bred for a little more cool weather tolerance might also help.
I've had luck with Sweet Banana peppers. It's a pretty common pepper to have success with around here. Technically they have some capsaicin (not none like bell peppers) but not enough for any significant heat. My elderly mom that doesn't like spicy can eat them raw on salads.
Last year I grew one Serrano pepper plant and had decent output despite 2023 being the summer of cool and overcast. The output was pretty similar to the Sweet Banana in weight - more but smaller peppers.
I tried two Pimento starts from a greenhouse the year before with normal weather. Maturity was short enough I had hope but they were flops. Maybe that was me. Maybe that was something about them not related to my climate. I didn't give them a second shot.
For bells, I tried California Wonder 300 last year but got 4 less than full sized peppers total off 2 plants. In theory, their DTM made me think I would have luck but again it was the "summer of cool and overcast." I'll probably try 1-2 again to see what more normal weather does.
I got King of the North to try this year. It's a red bell that supposedly does well in cooler northern climates.
I haven't tried it but supposedly black plastic mulch can help with their heat needs. It absorbs sun without providing the soil insulation you get from typical mulches. Just skipping any organic mulches like straw or grass in the early season and doing more weeding is also an option.
The host of the Gardening In Canada channel on Youtube recommends containers for peppers. She's in western Canada, without the Great Lakes effects, so likely closer to your conditions than mine or most of those on here. Supposedly people in her area get better output that way than in the ground. I assume the soil warming faster is the major driver. It's another thing I haven't tried so
.
Good luck.
