Peas tend to be largely trouble-free, but young plants are susceptible to slug and snail attack, as well as predation by mice, which love pea seedlings. Try a liberal sprinkling of chilli powder and/or holly bush prickles to help deter mice. Protective netting or horticultural fleece will protect your plants from air attack from birds – particularly pigeons – and also pea moths whose larvae attack the peas inside the pods. Attack by pea weevils will cause some notching of young leaves but should not do too much damage. Otherwise, keep an eye out for powdery mildew – adequate spacing of plants will aid with air circulation, making this less likely.