Potato problems

While potatoes are susceptible to a few serious, and a number of minor, pests and diseases that can affect yield and quality, pests specific to potatoes cannot survive for long if they don’t have access to them so don’t grow potatoes on the same ground more than one year in four, less frequently if possible.

Reduce the risk further by buying seed potatoes from a reputable source and selecting varieties that show resistance.

There are three serious pests – potato cyst eelworm, slugs and wireworm - and one serious disease – potato blight.

	Symptoms	Treatment	Prevention
Potato Cyst Eelworm	Plants look poor and stunted; upper leaves pale and wilt in daytime. Lower leaves wither. Marble sized tubers produced.	None. Burn all infected foliage and tubers.	Use a resistant variety and practice crop rotation.
Slugs		Use a biological control such as Nemaslug in mid-March and another six weeks later.
Wireworm	Tubers riddled with narrow tunnels.	None; this is often a problem on land that has recently been cultivated from grassland	Apply pirimiphosmethyl to the soil before planting
Potato Blight	More of a problem in wet years. Usually starts in August. Foliage develops brown blotches; if it is damp, the underside of the leaf will have blight spots with a white mould fringe. If the blight spores reach the tubers, they will rot.	None once the disease has taken hold.	Plant healthy seed potatoes. Choose a blight resistant variety. Spray with mancozeb in July and repeat fortnightly if the weather is damp. Keep the haulm earthed up. Destroy all infected haulms and tubers.

Previous « Plant care and harvest
Next Growing Carrots »

About Rosemary Champion

Rosemary lives on a 12 acre smallholding in Angus, in the east of Scotland, where she keeps Ryeland Sheep, Shetland cattle and assorted poultry. She was destined to be a smallholder from an early age.