Common Peas pests

Pea aphids are the top insect pest, small pale to bluish green soft-bodied insects that cluster on shoot tips, leaf undersides, and developing pods, causing curling, stunting, sticky honeydew, and the spread of viruses. Pea leaf weevils chew distinctive scalloped notches along leaf margins while their larvae feed on root nodules, and the pea weevil (Bruchus pisorum) lays eggs on pods so larvae bore into developing seeds, leaving round exit holes in dried peas. Pea moth and other small caterpillars tunnel into pods to feed on the peas inside, and in hot, dry spells thrips and two-spotted spider mites can stipple and bronze the foliage. Cutworms sever young seedlings at the soil line, and animal pests including birds pulling up sprouting seed plus rabbits, deer, and groundhogs grazing the vines can quickly strip a young planting.

Common diseases

Powdery mildew is the most common disease, showing as a white powdery coating on leaves, stems, and pods, usually late in the season as weather warms. Root and seed rots caused by Pythium, Aphanomyces, Fusarium, and Rhizoctonia lead to poor stands, damping-off of seedlings, and brown, soft roots, while Fusarium wilt yellows and wilts plants from the base up. The Ascochyta blight complex produces brown to purplish spots on leaves, stems, and pods along with a foot rot at the stem base, and bacterial blight causes water-soaked angular spots that dry to brown papery lesions, especially after cold, wet weather. Aphid-borne and seed-borne viruses such as pea enation mosaic, pea seed-borne mosaic, and bean leaf roll cause mottling, leaf distortion, blister-like enations, and overall stunting.

Prevention

Rotate peas and other legumes so they do not return to the same bed for three to four years, which starves out soilborne root rots, wilts, and weevils. Space plants and trellis climbing types so air moves freely and foliage dries quickly, and choose varieties labeled resistant to powdery mildew, Fusarium wilt, and pea enation mosaic where available. Plant into well-drained soil at the right cool temperature, water at the base in the morning rather than overhead, and avoid handling plants while they are wet to limit the spread of bacterial and fungal blights. Clean up and remove crop debris at the end of the season, and start with certified disease-free seed rather than saving seed from troubled plants.

Organic control

Cover young plantings with floating row covers from sowing to exclude aphids, weevils, pea moths, and hungry birds, and since peas self-pollinate the covers can stay on through much of the season. For aphids, first knock colonies off with a firm spray of water and encourage lady beetles, lacewings, and parasitic wasps, then step up to insecticidal soap, horticultural oil, or neem if numbers keep climbing, always reading and following the product label. Treat pod-feeding caterpillars with Bt (Bacillus thuringiensis) applied when small larvae are active, and hand-pick cutworms at dusk or use collars around seedling stems. For powdery mildew, apply sulfur early at the first white patches, and use a copper product for bacterial and some fungal blights, again following all label directions, while promptly pulling and discarding severely infected or virus-affected plants.

Scouting & monitoring

Scout shoot tips and leaf undersides at least weekly for aphids, since catching them early is the key to preventing virus spread. Watch for scalloped leaf-edge notching as seedlings emerge, a sign of pea leaf weevil, and check for gaps or collapsing seedlings that point to root rot or cutworms. As the weather turns warm and dry late in the season, inspect leaves for the first white powdery patches, and examine pods for entry holes, spotting, or tunneling as they fill. Note any yellowing, wilting, mottling, or distorted growth so you can remove problem plants before diseases move through the planting.

Tips

Plant early into cool soil and aim to harvest before summer heat, which lets you dodge the worst of powdery mildew and aphid buildup. Managing aphids well is your best defense against pea viruses, and never save seed from virus-infected or weevil-damaged plants.

General home-garden IPM guidance, focused on prevention and least-toxic control. Always read and follow the product label for any pesticide, including organic products. Page updated Aug 4, 2026.