Potatoes Growing Guide
Potatoes are a traditional veg plot staple, easy and fun to grow, producing plentiful crops in summer and autumn. The humble spud (Solanum tuberosum) comes in a surprisingly diverse range of varieties, offering gardeners a choice of flavours and textures not typically found in supermarkets. Most varieties are classed as either earlies (new potatoes) or maincrops, depending on their harvest time. They are grown from specially prepared ‘seed potatoes’ (small tubers), usually planted in spring.
This guidance applies to the crop in general. Individual varieties and local conditions can differ.
Planting information
Potatoes are grown from specially prepared ‘seed potatoes’ (small tubers). For early varieties, seed potatoes can be ‘chitted’ (encouraged to sprout) before planting to produce an earlier crop. Start chitting early varieties in late January (milder areas) to early March (colder spots); the process takes four to six weeks. There is no real advantage to chitting maincrop varieties. Chitting is not essential but can give an early start. Potatoes are mainly planted in spring: First earlies around late March; Second earlies in early to mid-April; Maincrops in mid-April to early May. Timing depends on the region. To plant in the ground, dig a trench 15cm deep, place seed potatoes along the base with sprouts upwards, cover with at least 2.5cm of soil, and water well. For Earlies, plant 30cm apart in rows 60cm apart. For Maincrops, plant 37cm apart in rows 75cm apart. Practice crop rotation annually. For no-dig gardens, shallow-plant seed potatoes and add a deep layer of organic matter on top. For container planting (container at least 30cm wide and deep), half-fill with 15cm of peat-free multi-purpose compost. Plant one seed potato per 30cm pot diameter just below the surface. Gradually add more compost as shoots grow until just below the rim. Can also be grown in potato grow bags or sacks with drainage holes.
Harvesting information
Early potatoes (First earlies: June-July; Second earlies: July-August) are ready when flowers open or buds drop, and tubers are the size of hens’ eggs. Maincrop varieties are ready from late August through to October. For immediate use, lift maincrops in late summer. For storing, delay harvesting until leaves turn yellow, then cut off all top growth. Wait for 10 days, then dig up the tubers and leave them in the sun for a few hours to dry, then brush off the soil. Dig carefully, inserting a fork at least 30cm away from the base of the plant to avoid damaging tubers. Discard any green potatoes. For individual potatoes, gently dig beside a plant with a trowel without disturbing roots. Potatoes grown in containers are easy to harvest by gently tipping out the contents and picking them by hand. Early potatoes are best used as soon as possible after harvesting.
Storage information
Maincrop potatoes usually store successfully for several months. Only store undamaged, dry potatoes; brush off any soil before storing. Keep them in a dry, cool, frost-free place (e.g., garage) in paper or hessian sacks or on slatted trays in the dark (to prevent sprouting). Check them every few weeks for signs of rotting. Aim to finish them before early spring, as they will start to sprout and shrivel.