Also known as Sunchoke. The fresh tuber tastes like a water chestnut; it can be used in salads or cooked in the same way as potatoes. It is a member of the sunflower family.
These are tall growing, able to reach a height of almost 7 ft (210cm). They also require well-drained soil in a warm and dry position. They need soil that contains plenty of manure and compost so that large tubers can develop. At the time of planting apply fish manure at 2 oz. (60g) to the sq. yd. Wood ash is also excellent at this time at 5 oz. (150g) to the sq. yd.
Plant the tubers, which should be the size of hen’s eggs, in March or early April. Using a draw hoe, take out a furrow 6 in. (15cm) deep and spread well-rotted manure or compost evenly along the bottom. The tubers should be planted about 1 ft. apart in the furrows, then cover them, leaving a ridge about 2 in. (50mm) high over the top. Organic fertilizer can be sprinkled over the top at this stage fish manure is suitable. If you intend to plant more furrows they should be about 3 ft. (90cm) apart.
When the plants have grown to 1 ft. (30cm) high, use a hoe to draw up the soil to them. This should be done about every 2 weeks until the rows are earthed up 6 in. (15cm) or more. As these plants are tall growing it is advisable to give them some support so that high winds cannot blow them over. This can be in the shape of 6 ft. poles driven into the ground at each end of the row on both sides; wires can then be stretched between them. The tubers should have developed by the end of October so the tops of the plants can be cut down to within 2 ft. (60cm) of the soil.
You do not have to lift them immediately, for the Jerusalem artichoke is quite hardy, the tubers can be left in the ground until you are ready to use them. They can remain in the ground until late November when they should be dug up and left covered with 6 in. (15cm) of straw, and the same amount of soil. It is very important that all the tubers are dug up after harvesting, otherwise, these will cause weed problems the following year.