As pretty as they can sometimes be, primulas seem to pop up everywhere
in my garden almost as invasively as weeds, yet after a cursory web
search I read quite a bit of advice about digging them up after
flowering, dividing them and then replanting. This seems quite an
elaborate procedure for something that survives all to happily without
any intervention from me. Am I'm missing something?

Can anyone advise. Just leave them be? Can one trim of the leaves
before they start to yellow and become unsightly?

thanks for any help.