Jerusalem Artichoke Association of Canada
Characteristics of the Jerusalem artichoke
The Jerusalem artichoke (Helianthus tuberosus) is an herbaceous perennial plant of the genus Helianthus (sunflower) in the family Asteracea (daisy). The flowers are yellow resembling closely those of the common sunflower but are smaller and are found at the end of the stems and axillary branches. The leaves, covered with hairs, have an oval to lance shape with coarse tooth edges. Its stout stems are 1-3 metres in height and become coarse with age.
The plant reproduces by seeds and by fleshy rhizomes (unground stems) that bear small potato-like tubers. The seeds of the Jerusalem artichoke plant are usually low in number thus the tubers are the main mechanism by which it reproduces. The tubers survive through winter and germinate in late spring. Flowers start to appear in August, till October. One single Jerusalem artichoke plant can produce as many as 200 tubers but typically produce around 75 tubers.
Jerusalem artichoke tubers vary in size and shape from small, round and knobby to long, slender and smooth.They can also vary in colour from white, yellow, pink or red. Typically, they resemble gingerroots or knobby potatoes. In many cultivars, the tubers are 5-8 cm across and up to 10 cm long. Wild strains of Jerusalem artichokes produce slender red-skinned tubers that are enlarged at their tips. The cultivated strains, the tubers are larger, crisp-fleshed, white or yellowish and often tinged with pink, purple or red-skinned. White-skinned strains include the early maturing “Stampede” or mid-season maturing “Challenger” which produce crisp round and pear-shaped tubers respectively. The “Columbia” cultivar is the highest yielding cultivar grown in Canada but produce large knobby clusters of tubers that are difficult to clean. The “White Fuseau” variety grow more slowly, and the resulting tubers are longer, and thus easier to scrub and peel. The “Red Fuseau” has red skin roots with few attached round nodules, making them easy to clean. Other red varieties including “Red Rover” and “Waldspinel” are longer and often called “fingerling sunchoke”. But more often, Canadian grocery stores and garden catalogs simply sell the tubers under the name “Jerusalem artichokes”.