No flowers:P-K Feed ? Still too early/small?

Dear chilli growers,

I love chillies but in my cold northern German climate and a three month long summer I never could grow them. This year at least they didn't die as seedlings. They (some variety of birds eye)are about 30cm but there are no flowers. Do you see any red flags? Should I change feed, or just wait patiently?

I try to not water too often. The soil is horse manure based compost which drains reasonably.

Any help will be greatly appreciated.