Common Name: Jerusalem Artichoke

General Information

Helianthus tuberosus is an erect herbaceous perennial plant growing from a tuberous rootstock; it can grow 50 - 200cm or more tall, spreading to form large clumps[].
Jerusalem artichokes were a common food for the Native Americans, and are sometimes cultivated as a food crop, especially in Europe. It is still harvested from the wild for local use as a food, medicine and source of materials.
Often cultivated as a food crop in Europe, the plant has escaped from cultivation and become naturalized through most of Europe and also in many other temperate regions of the world.The plant is classified as 'W' in the IUCN Red List of Threatened Species(2013)[].

Known Hazards

None known

Botanical References

, ,

Range

Central and eastern N. America - Saskatchewan to Quebec, south to Texas and Florida

Habitat

Rich and damp thickets[]. Roadsides, fields, waste areas; at elevations up to 1,000 metres[].

Properties

Weed Potential	Yes
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Perennial
Height	1.80 m
Growth Rate	Fast
Pollinators	Bees, Flies
Cultivation Status	Cultivated, Wild

Cultivation Details

Jerusalem artichoke is reported to tolerate an annual precipitation of 31 to 282cm, an average annual temperature of 6.3 to 26.6°C and a pH in the range of 4.5 to 8.2[].
A very easily grown plant, it grows best in a loose circumneutral loam but succeeds in most soils and conditions in a sunny position[, , , , ]. Plants are more productive when grown in a rich soil[, , ]. Heavy soils produce the highest yields, but the tubers are easily damaged at harvest-time so lighter well-drained sandy loams are more suitable[]. Dislikes shade[]. Likes some lime in the soil[].
Jerusalem artichokes were cultivated as a food plant by the N. American Indians and they are today often grown in temperate areas for their edible tubers. There are some named varieties[, , , ]. The plant is a suitable crop in any soil and climate where corn (Zea mays) will grow. It survives in poor soil and in areas as cold as Alaska. It also tolerates hot to sub-zero temperatures[]. The first frost kills the stems and leaves, but the tubers can withstand freezing for months[]. The plants are particularly suited to dry regions and poor soils where they will out-yield potatoes[]. Tuber production occurs in response to decreasing day-length in late summer[]. Yields range from 1 - 2kg per square metre[]. The tubers are very cold-tolerant and can be safely left in the ground in the winter to be harvested as required. They can be attacked by slugs, however, and in sites prone to slug damage it is probably best to harvest the tubers in late autumn and store them over the winter. It is almost impossible to find all the tubers at harvest time, any left in the soil will grow away vigorously in the spring.
Plants do not flower in northern Europe. They are sensitive to day-length hours, requiring longer periods of light from seedling to maturation of plant, and shorter periods for tuber formation. They do not grow where day-lengths vary little[].
The plant is good weed eradicator, it makes so dense a shade that few other plants can compete[].
The young growth is extremely attractive to slugs, plants can be totally destroyed by them[].
Members of this genus are rarely if ever troubled by browsing deer or rabbits[].
Plants only produce flowers in Britain after a long hot summer[] and seed is rarely formed[].
Grows well with corn[].
Plants can be invasive[].

Edible Uses

Tubers - raw or cooked[, , , ]. The tuber develops a pleasant sweetness during the winter, especially if subjected to frosts, and is then reasonably acceptable raw[]. Otherwise it is generally best cooked, and can be used in all the ways that potatoes are used[]. The tubers are fairly large, up to 10cm long and 6cm in diameter[].
The tubers bruise easily and lose moisture rapidly so are best left in the ground and harvested as required[].
The tubers are rich in inulin[], a starch which the body cannot digest, so Jerusalem artichokes provide a bulk of food without many calories[]. Some people are not very tolerant of inulin, it tends to ferment in their guts and can cause quite severe wind[].
The inulin from the roots can be converted into fructose, a sweet substance that is safe for diabetics to use[, ].
The roasted tubers are a coffee substitute[].

Medicinal

The plant is reported to be aperient, aphrodisiac, cholagogue, diuretic, spermatogenetic, stomachic, and tonic. It is a folk remedy for diabetes and rheumatism[].

Agroforestry Uses:

A fast-growing plant, Jerusalem artichokes can be grown as a temporary summer screen[]. Very temporary, it is July before they reach a reasonable height and by October they are dying down[].

Other Uses

The plants are a good source of biomass. The tubers are used in industry to make alcohol etc[]. The alcohol fermented from the tubers is said to be of better quality than that from sugar beets[].

Propagation

Seed - sow spring in a cold frame. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts.
Division in spring or autumn[]. Harvest the tubers in late autumn or the winter and either replant the tubers immediately or store them in a cool but frost-free place and plant them out in early spring. Jerusalem artichoke is propagated by tubers, which should be planted as early as possible in the spring when the soil can be satisfactorily worked[]. Late planting usually reduces tuber yields and size seriously. Whole tubers or pieces about 50 g (2 oz.) should be planted like potatoes and covered to a depth of 10 cm. Pieces larger than 50 g do not increase the yield, though those smaller will decrease it. Deeper planting may delay emergence, weaken the sprouts, and cause the tubers to develop deeper, making harvest more difficult[].
Basal cuttings in spring. Harvest the shoots when they are about 10 - 15cm long with plenty of underground stem. Pot them up into individual pots and keep them in light shade in a cold frame or greenhouse until they are rooting well. Plant them out in the summer.