The Jerusalem artichoke has never been a widely grown vegetable, a position shared by its namesake, but no relation, the globe artichoke.
Its botanical name is Helianthus tuberosus, making it a close relative of the annual sunflower, as can be seen from its habit - it will reach 6ft or more – and its foliage.
The ‘Jerusalem’ part of its name is misleading, as it is a native of North America, where it still grows wild from Nova Scotia to Kansas. The common name is actually a corruption of the Italian ‘girasole’.
I sense, however, that Jerusalem artichokes are gaining in popularity. They are very easy to grow and certainly worth trying, especially if you would like a temporary shelter or screen in addition to a crop of small, versatile tubers.
Peeled and boiled, they can be eaten as a hot vegetable, just like potatoes, or made into a satisfying soup. Incidentally, the main storage carbohydrate in the tubers is inulin rather than starch and they are therefore a valuable carbohydrate source for diabetics.
The Jerusalem artichoke was introduced to Europe in the early 17th century and it does well in a wide range of soils, even poor, dry ones where potatoes do not thrive. Tubers can be planted in spring and they are widely available in the seedsmen’s catalogues.
Choose the variety Fuseau over the common form, as its tubers are much smoother and easier to prepare for cooking. The taste is just as good. Plant the tubers 3in deep and 18in apart in the row. Allow 3ft between rows. The tubers become ready for lifting in the autumn, as day length decreases, and harvesting can continue through winter as long as soil conditions permit.
Jerusalem artichokes are best harvested shortly before needed in the kitchen, as they bruise easily and quickly lose moisture in storage. They are perennial and the tubers can be left in the ground for more than one season, but because they are liable to spread it is advisable to treat them as an annual crop and lift all the tubers every autumn, re-planting in spring.