Few crops feel as rewarding to grow as your own potatoes, lifting a fork to find a clutch of clean tubers hidden in the soil. Maincrops, the ones that store through winter, go in a little later than the earlies and crop heavily for the effort.
When and where
Plant maincrops from mid-spring, once the soil has warmed and the worst frosts are past. They want an open, sunny spot and ground enriched with plenty of compost or rotted manure, as potatoes are hungry plants.
Planting the rows
Maincrops need more room than earlies because they make a bigger plant and a heavier crop.
- Plant tubers about fifteen centimetres deep.
- Space them a generous thirty-eight centimetres apart.
- Leave around seventy-five centimetres between the rows.
Earthing up
As the shoots reach about twenty centimetres, draw soil up around them from both sides into a ridge, leaving just the tips showing. Repeat as they grow. This protects early shoots from frost and stops light reaching the tubers, which turns them green and inedible.
Water and wait
Keep them watered in dry spells, especially once the plants flower and the tubers are swelling. Maincrops are usually ready from late summer; cut the foliage down, leave them a fortnight to set their skins, then lift on a dry day for storing.