Autumn sowing of Beans and Peas

Now then, everyone. Seeing were on the subject of peas. How do you avoid pea moth grubs in peas grown outside? I've tried with fleece but it was a faff on tall growing types and I'm not sure it doesn't prevent pollination. I resorted to mangetout because then you don't see the grubs, if any, and what the eye doesn't see, etc.