Distribution and biology of potato volunteer weeds in the UK
Potato can occur as a volunteer weed from previous crops or domestic waste. Green parts of the plant are poisonous to humans and livestock. Find out how to identify and control it.
Volunteer potatoes (Solanum tuberosum) can be very competitive weeds in subsequent crops. They develop from tubers left in the soil or as seedlings from true seeds in spring.
- It is particularly competitive in spring crops
It is an upright dicotyledon up to 1 m high, with stolons developed into tubers at or just below the soil surface. It is very robust, with leaves divided in oval leaflets. Flowers are white or purple. The plant may develop large spherical poisonous fruits that resemble green tomatoes.
It contains the poison solanine, in the green parts of the plant and in tubers exposed to light, which can be fatal to humans and livestock.
Location and life cycle
Potato usually occurs as volunteers from previous cropping and so is most likely to be found in the arable areas to the east of the British Isles. It also grows in areas where domestic waste has been left.
Potato prefers sandy loams, silt loams, loams and peat soils.
- Seeds/plant: 50–200
The best control is good harvesting practice in potato crops. In cereal crops, sulfonylureas have an effect in reducing further tuber growth. Pre-harvest treatment with glyphosate is effective if the plants are still green. In most vegetable crops, fruit crops and legumes only physical control is possible. Otherwise using glyphosate at or near flowering of potato plants is the most effective chemical treatment. Potatoes do not persist in dense crops such as oilseed rape or grassland.