Growing in the ground
Potatoes do best in a sunny position on fertile and well-drained soil. You should avoid planting in the same position each year as this increases the risk of disease – ideally use a 4 year crop rotation cycle.
Prepare the soil by removing weeds and stones and then digging in plenty of well-rotted organic material (manure and/or compost).
Planting times are dependent on weather, soil conditions, regional variations and the type of potato but generally plant March to late May – first earlies to start followed by second earlies and then early and late main crop varieties.
Dig a trench about 6 inches deep and place the seed potatoes into the trench with the end with the chits (the ‘rose end’) facing upwards. Fill the trench with soil to cover the potatoes.
• First Earlies – plant 12 inches apart in rows 2 feet apart
• Second Earlies – plant 15 inches apart in rows 2 feet apart
• Maincrop – plant 18 inches apart in rows 2.5 feet apart
Potatoes should be ‘earthed-up’ as the shoots emerge from the ground to protect them from frost, which will blacken the shoots and slow growth. Draw soil over the top of the plant with a hoe.
It’s a good idea to earth-up the plants again when the stems are about 9-12 inches above ground as this will prevent potatoes near the surface of the soil turning green and also helps stop spores from any blight (a disease affecting potatoes – brownish black spots appear on leaves and stems) being washed into the soil and affecting the tubers.
Tubers exposed to sunlight will turn green. Don’t eat green potatoes – they contain a toxic alkaloid, which can cause vomiting and stomach upsets. The leaves and tomato like fruits are also poisonous.