I have loads of green shield beetles on my calendulas, which I thought was supposed to be a good companion plant. Should I be happy that they are on the dead flower heads and not so much on the beans and therefore leave the flowers there? I do knock them off into boiling water which is very effect at reducing the population.
It’s unusual that green shield beetles are on your calendulas and not eating up your beans, but that’s a good thing. So leave your calendulas as they are, and get rid of as many of the green shield beetles as you can. Dropping the beetles into boiling water is a good method, as is dropping them into a solution of water with a splash of methylated spirits. Alternatively just squish them with your fingers – the smell they emit when squished detracts others. Good luck!