Peas: Pests & Diseases
Peas are a rewarding cool-season crop for British gardens and allotments, producing sweet pods or shelled peas from late spring into summer. They grow best in an open, sunny bed with moisture-retentive soil, sturdy supports and regular picking. Young plants need particular protection from pests.
Common pests
Pea moth is most troublesome in later sowings, leaving creamy maggots and frass inside developing pods. Pea and bean weevil makes distinctive scallops along leaf edges, especially on young plants. Pea aphid can crowd stems and flower buds, while mice may dig up and eat sown seed. Pigeons and other birds can pull out seedlings or peck at tender growth. Slugs also damage emerging shoots in damp weather.
Common diseases
Powdery mildew is common late in a dry summer, coating leaves with pale powdery growth and reducing vigour. Downy mildew causes yellowish patches with greyish growth beneath leaves in cool, damp conditions. Pea wilt can cause sudden yellowing and collapse, particularly in repeatedly used ground. Foot rot and other root rots lead to poor emergence, brown stem bases and stunted plants, especially where soil is cold, compacted or waterlogged.
Prevention
Rotate peas and other legumes around the plot, avoiding the same ground for several years where wilt or root rot has occurred. Sow into warm, free-draining soil and space plants so air moves through the row. Choose varieties with useful disease tolerance where available. Use pea sticks or netting supports to keep foliage upright, remove crop debris promptly, and cover fresh sowings with cloches or mesh where mice are active.
Non-chemical control
Hand-pick weevils where numbers are high and remove heavily aphid-infested shoot tips. Encourage hoverflies, ladybirds and lacewings with nearby flowers and avoid disturbing their larvae. Protect germinating seed with cloches, and use fine netting to deter pigeons. Check traps or sheltered boards for slugs and remove them regularly. If pea moth has been a recurring problem, sow early where practical and pick pods frequently before larvae mature.
What to look for
From sowing onwards, check for missing seed, disturbed soil and clipped seedlings. Inspect leaf margins weekly for weevil notches and growing tips for pea aphid colonies. From flowering, open a few swelling pods to look for pea moth damage. In humid spells, examine lower leaves and stem bases for mildew, yellowing or rot.
Tips
Water during flowering and pod fill, especially on light soils, then harvest every few days to keep plants productive. Do not compost plants showing serious wilt or root rot. For a longer season, sow small batches rather than one large row.
Peas pests & diseases: frequently asked questions
What are the common pests of peas?
Pea moth is most troublesome in later sowings, leaving creamy maggots and frass inside developing pods.
What diseases affect peas?
Powdery mildew is common late in a dry summer, coating leaves with pale powdery growth and reducing vigour.
How do I prevent pests and diseases on peas?
Rotate peas and other legumes around the plot, avoiding the same ground for several years where wilt or root rot has occurred.
General guidance for UK home gardens, focused on prevention and non-chemical control. The RHS or a local garden centre can help with tricky cases. Page updated 18 Sep 2026.