Guide to Growing Potatoes
Find out how to plant potatoes and reap a delicious harvest.
2012, Dorling Kindersley Limited
Growing potatoes is easy, even in small spaces and containers. What's more, the humble spud comes in myriad shapes and colors and has many uses in the kitchen, from summer salads to all-season chips.
How to Grow
Potatoes need an open, sunny site with moist, well-drained, fertile soil, improved with plenty of well-rotted organic matter, such as garden compost. Sold as “seed” potatoes (small tubers), they are labeled as “earliest,” “mid-season,” or “late,” depending on when they are ready to harvest.
For an early start, cover the planting area with sheet plastic to warm the soil, and plant the tubers through it. This also retains moisture and suppresses weeds. Once “chitted”, plant earliest potatoes after the frost in the spring; mid-season in mid-spring; and late types from mid- to late spring. Plant the tubers 4–6 inches (10–15 cm) deep, and cover the chits with 1 inch (2.5 cm) of soil. Space them 12 inches (30 cm) apart with 24 inches (60 cm) between rows for earliest, 30 inches (75 cm) for late types. Keep plants well watered, weed regularly, and “earth up” as needed.
Harvest earliest types in early summer, scraping away some soil first to see if they are large enough. Mid-season will be ready in midsummer, and lates from late summer to fall. Unearth them with a fork, taking care not to spear them. Clear all plant debris from the soil.
Types and Varieties of Potatoes
- Earliest: Try ‘Accent’, ‘Concorde’, ‘Epicure’ ‘Foremost’, ‘Pentland Javelin’, ‘Red Duke of York’, ‘Swift’, ‘Vivaldi’ and ‘Winston’ varieties.
- Mid-season: Try ‘Belle de Fontenay', ‘Charlotte’, ‘Estima’, ‘Kestrel’, ‘Kondor’, ‘Lady Christl’, ‘Picasso’, ‘Ratte’ and ‘Yukon Gold’ varieties.
- Late: Try ‘Desiree’, ‘Golden Wonder’, ‘King Edward’, ‘Maris Piper’, ‘Navan’, ‘Nicola’ ‘Picasso’, ‘Pink Fir Apple’ and ‘Salad Blue’ varieties.
Garden Speak: "Chitting" Potatoes
Early potatoes can be “chitted” before planting, which involves giving them an early start indoors. To do this, place the seed potatoes with their “eyes” facing upward in trays or egg boxes in a warm, light place so that short green shoots, or “chits,” appear. Once the chits are 1/4- to 1/2-inch (5–10 mm) long, the tubers are ready to be planted out.
When the developing stems reach 6in (15cm) tall, start “earthing up” by mounding up the surrounding soil to cover the shoots, burying them by half their height. Repeat every few weeks as the shoots grow. This prevents tubers being exposed to sunlight, which turns them green and makes them poisonous. It also helps stifle weeds and deters blight. Potatoes grown through black plastic sheeting don’t require earthing up. Earth up potatoes carefully to avoid damaging the stems, which are brittle at the base and can snap. Earthing up also prevents wind damage.
Growing in Containers
If you don’t have much space, you can grow a decent crop of potatoes in a container or strong bag. Ensure that it is at least 12 inches (30 cm) deep with drainage holes, and half-fill it with compost. Place one or two potatoes on top and cover with 4 inches (10 cm) of compost. Add compost to half-cover the shoots as they grow, and water regularly. Harvest the potatoes as soon as they are ready. This method is suitable for all crops. New potatoes are ideal for growing in strong plastic bags. Harvest the crop by tipping the potatoes out once they have matured.
If you’re not sure when to harvest potatoes, look for tell-tale signs above ground. Earliest varieties are ready when their flowers begin to open or the buds drop. Late crops are ready when their foliage yellows, although they can be left in the soil until mid-fall to bulk up. Cut back stems 10 days before lifting. Open flowers mean that the earliest are ready to lift, but late crops still need time to grow.
Storing Late Potatoes
Lift potatoes on a dry day, and leave them to dry on the soil surface. Discard any that are diseased or damaged, and use smaller tubers fresh since they deteriorate sooner. Once the skins are dry, remove excess soil, but don’t clean them further to prevent damaging the skins. Store the tubers in paper bags or in trays, somewhere dry, well ventilated, and frost-free. Check them often for damage or decay.
Watch Out for These Pests and Diseases
Potato cyst eelworms cause leaves to yellow and plants to die off early, reducing the crop. There is no control, but it helps to rotate crops, and use resistant varieties. Another problem that can plague potatoes is blight, which causes dead patches on the leaves and stems and on the tubers, which then rot. It is prevalent in damp summers, so if the season starts wet, spray plants with fungicide. Destroy infected plants.