What pests attack potato?

Colorado Potato Beetle, Tomato russet mite, Broad mite, Chafer grubs, Flea beetles, Leaf Miner, Tomato hornworm, Wireworms

What diseases affect potato?

Bacterial soft rot, Bacterial wilt (brown rot of potato), Late Blight, Potato blackleg, Tomato spotted wilt virus, White mould (Sclerotinia), Black scurf, Early Blight, Verticillium wilt, Common scab

Potato pests and diseases: how to recognise them

Q: Which potato problems need quick action?

Colorado Potato Beetle: Oval yellowish beetles about 1 cm long with ten black stripes on their wing covers. Tomato russet mite: Fruit skin turns bronze and may crack lengthwise. Bacterial soft rot: Whole roots, tubers, bulbs, heads or fruit can collapse within a few days, often leaving only the skin — in the garden and in storage. Bacterial wilt (brown rot of potato): The youngest leaves wilt first, then the whole plant wilts quickly in warm weather while the leaves stay green, even though the soil is moist. Late Blight: Pale green to brown spots with water-soaked edges on the leaves that spread fast; leaves collapse, shrivel and turn brown, and stem lesions are brown to almost black. Potato blackleg: Early in the season, some stems are stunted and pale green or yellow, with yellow leaves. Tomato spotted wilt virus: Fruit with pale yellow or light green rings, often raised in the centre; ripe tomatoes blotched red and yellow; peppers with ring spots. White mould (Sclerotinia): Later, hard black seed-like bodies (sclerotia) 0.5–1 cm across in the mould and inside hollow stems.

Solanum tuberosum

The pests, diseases and disorders recorded for potato in our library, each with a photo and its first symptom. Every page has the full list of symptoms, organic and chemical treatment and prevention.

At a glance

Problems in total	18
Pests	8
Diseases	10
Need quick action	8

How to grow potato · All pests and diseases

Pests

Colorado Potato BeetleOval yellowish beetles about 1 cm long with ten black stripes on their wing covers.Also called: Colorado beetle, potato bugPhoto: Adámozphoto, CC BY-SA 4.0, Wikimedia Commons
Tomato russet miteFruit skin turns bronze and may crack lengthwise.Photo: Goldlocki, CC BY-SA 3.0, Wikimedia Commons
Broad miteGrowing tips and buds are killed and new growth is stunted — easily mistaken for disease or herbicide damage.Photo: David Riley, University of Georgia, Bugwood.org, CC BY 3.0, Wikimedia Commons
Chafer grubsPotatoes, beetroot and other root crops have large, shallow, round holes.Photo: Сарапулов, CC BY 4.0, Wikimedia Commons
Flea beetlesSeedlings and fresh transplants are hit hardest and can be stunted; older plants are rarely harmed unless beetles are numerous.Photo: Bob Peterson from North Palm Beach, Florida, Planet Earth!, CC BY-SA 2.0, Wikimedia Commons
Leaf MinerHeavily mined leaves dry up or drop early; badly affected tomato plants can lose most of their leaves.Photo: Flowersabc, CC BY-SA 2.0, Wikimedia Commons
Tomato hornwormThick green caterpillars up to 10 cm long with a horn at the rear end and eight white V-shaped stripes on each side; the similar tobacco hornworm has seven diagonal stripes.Also called: five-spotted hawkmothPhoto: Whitney Cranshaw, Colorado State University, Bugwood.org, CC BY 3.0 us, Wikimedia Commons
WirewormsThin, yellowish-brown larvae up to 25 mm long with three pairs of short legs behind the head in the soil.Photo: Alton N. Sparks, Jr., University of Georgia, Bugwood.org, CC BY 3.0, Wikimedia Commons

Diseases

Which potato problems need quick action?

These spread or do lasting harm fast; check the plants and start treatment the day you see them.

Colorado Potato Beetle: Leaves eaten down to the stems; heavy attacks can strip potato plants completely.
Tomato russet mite: No webbing; the mites are too small to see without a strong hand lens. Untreated plants can die in hot, dry weather.
Bacterial soft rot: Potato stems may turn black and rot from the base upwards (blackleg).
Bacterial wilt (brown rot of potato): Potato tubers have a brown ring under the skin when cut, with creamy ooze appearing on it after a few minutes; ooze can also come out of the eyes, so soil sticks to them.
Late Blight: Pale green to brown spots with water-soaked edges on the leaves that spread fast; leaves collapse, shrivel and turn brown, and stem lesions are brown to almost black.
Potato blackleg: Tubers rot — the flesh turns grey or brown and soft, with the decay spreading from the stolon end.
Tomato spotted wilt virus: Plants infected young often fail to flower or set fruit. There is no cure once a plant is infected.
White mould (Sclerotinia): Roots, heads, pods and fruit can rot too, also in storage.

Plants with many of the same problems

Which plants each problem affects: sources

The links between these problems and the plant were checked against these pages.