General
Jerusalem artichoke (Helianthus tuberosus) is a hardy, perennial sunflower grown for its edible, knobbly tubers rich in inulin. It forms tall, bamboo-like canes and spreads by underground rhizomes. Very cold-hardy and drought-tolerant once established, it can become invasive if not contained. Grown as a perennial patch or as an annual crop from tubers. Flowers are small, yellow sunflowers late in the season. Tubers are sweetest after frost and have a nutty, artichoke-like flavor.
Light
Full sun (6–8+ hours). Tolerates light partial shade but yields best in full sun.
Soil type
Loose, well-drained loam or sandy loam rich in organic matter; avoid heavy, waterlogged clay.
Water requirement
Moderate. Keep evenly moist during active growth and tuber bulking; mulch to conserve moisture.
Nutrient requirement
Low to moderate. Responds well to compost; avoid high-nitrogen fertilization which promotes tall, lanky growth over tubers.
Precultivation
For an early start in cool regions, pre-sprout (chit) tubers indoors 2–4 weeks before planting: place sound, egg-sized tubers in a bright, cool spot (10–15°C) on barely moist medium until 1–2 cm sprouts appear. Cut large tubers into pieces with at least 2 eyes; let cuts callus for 1–2 days before planting. Pre-sprouting reduces field time and helps in cold springs.
Planting
Plant outside when the soil is workable and risk of hard frost has eased. Space 30–45 cm between plants and 75–100 cm between rows. Plant 10–15 cm deep with sprouts pointing up. Work in 3–5 cm of mature compost; avoid fresh manure. Choose a sunny, sheltered site or use the plants as a living windbreak on the north edge of the plot. Install root barriers (spade-cut trench or buried edging 30–40 cm deep) to limit spread. Mulch after emergence to suppress weeds and retain moisture.
Pruning
Top plants at 150–180 cm in mid-summer to reduce windthrow and direct energy into tubers. Remove flower buds in August if maximum tuber yield is desired (flowers are ornamental but divert some energy). Cut spent stems to 10–20 cm after frost; the stubble traps snow and protects crowns.
Maintenance
Water steadily during dry spells, especially from mid-summer through early autumn when tubers bulk; erratic moisture causes knobbly or hollow tubers. Mulch 5–10 cm with straw or leaves. Stake or tie plants in windy sites. Side-dress lightly with compost or a balanced organic fertilizer in mid-summer if growth is pale. Scout for slugs on young shoots, wireworms in new ground, and powdery mildew late season (usually cosmetic). Rogue out volunteer shoots beyond the bed and maintain root barriers annually.
Harvest
Begin harvest after the first hard frost for best sweetness, typically October–November. Loosen soil with a fork and lift carefully to avoid breaking tubers. Leave a portion of small tubers in the ground for next year if you want a perennial patch. In mild areas or under a thick mulch, tubers can be dug all winter until the ground freezes; they also keep well in the soil into early spring. For storage, keep unwashed tubers in perforated bags at 0–2°C and high humidity; they wilt quickly at room temperature. Peel just before cooking.
Common issues
Spreading/invasiveness—contain with barriers and lift stray rhizomes. Windthrow—tall canes may lodge; top or stake. Powdery mildew late season—usually cosmetic; improve airflow. Sclerotinia/white mold—rotate 3–4 years and avoid waterlogged soils. Wireworms and voles may damage tubers—use traps, cultivate fallow ground before planting, encourage predators. Knobbly or hollow tubers result from drought or uneven watering.
Pollination
Insect-pollinated flowers (bees), but pollination is not required for tuber production.
Companion plants
Sweet corn (windbreak synergy), bush beans, peas, calendula, dill. Plant on the north edge to avoid shading shorter crops.
Incompatible plants
Avoid close rotation with potatoes and tomatoes (disease/pest overlap). Keep distance from delicate crops that dislike root competition.
