Tall peas

I would think picking regularly when it comes to it & maybe a feed or two

Now I know why people do not grow old tall varieties. My Show Perfection are covered in powdery mildew today. Hurst Green Shaft adjacent completely clear.

I have dusted them with sulphur so lets hope the pods fill before the mildew gets them.

Any other treatments work?

I am a big fan of tall peas as well.  You usually get more peas per row than shorter types.  I have had lots of success in the past with Champion of England and Sutton's Purple Podded.  This year I am growing Magnum Bonum.  This has not been quite so successful, but like MoS I put it down to the dry growing conditions this spring.   Still OK though.

My slightly shorter peas, Stokesley and Rosakrone have also done OK but yields have not been as prolific as usual in the case of Stokesley.  I haven't grown Rosakrone before this year, they are very pretty indeed but pods are small but taste good.  Quite unusual growing habit too, about 4' tall and all the salmon pink and white bi colour flowers are in a circle (crown) at the top of the plant.