Sweet potatoes are traditionally growing in warm climates, but hardier varieties are now becoming available in the UK and can be grown quite easily as long as they are grown in a warm sheltered spot.
Sweet potatoes are best grown from ‘slips’. These can be ordered from mail order companies generally in the spring. When they arrive, plant them into small pots and keep the compost moist. Cover them with a propagator until they root.
It is possible to grow sweet potatoes using shop bought tubers. However they are normally sprayed with an anti-sprouting agent so they will need to be cleaned before they can be used. Simply place the tuber in sand in a propagator until shoots start to show. Once the shoots are roughly 3 inches long, remove them from the tuber and pot them on as you would if you bought slips.
Sweet potatoes are best grown indoors in a greenhouse or poly tunnel. Simply transplant the slips into large tubs or a border and keep them well watered and feed every couple of weeks with a high potassium feed. If you are growing them outdoors, plant them in a warm sheltered spot and protect from frost.
The tubers take around five months to mature and are generally ready when the leaves turn yellow. Simply dig them up carefully to avoid bruising and use quickly, as they don’t store very well.