sunchoke / Jerusalem artichoke

Photo: Unknown — CC BY-SA 3.0 · source

Survives zone 3 through 9

Harvest calendar

Best planted in early spring after your last frost, or in fall before the ground freezes, depending on your climate.

Sunchoke — nutty, sweet, crisp. Excellent, but notoriously gas-forming.

Spread warning. Flagged as a high invasion risk by the California Invasive Plant Council and documented as weedy/invasive across much of its introduced range worldwide. Spreads both by seed (bird-dispersed) and by tubers — any small tuber fragment left in the soil resprouts, which is what makes an established patch so hard to fully remove. Site deliberately (a bottomless container or a bed with a hard physical edge well below the surface) rather than in open ground you might want back.

Hardiness

Zone 3–9

Habit

Herb

Edible part

Root

Ripens

Autumn–winter (tubers)

Mature size

2–3 m tall; container recommended — see spread warning

Light

Full sun

Soil pH

5.8–7.0

Environment

Temperate

Native range

Eastern and central North America, on riverbanks, damp thickets and disturbed ground. Nothing to do with Jerusalem: the name is a mangling of girasole, Italian for sunflower, and the plant has never grown wild anywhere near it.

Status

Both wild and cultivated

Years to fruit

1 yr

Growth speed

Very fast — 2–3 m of stem in a single season

Spacing

45 cm (18 in) apart — about 4.9 per m² (4.6 per 10 sq ft)

Leaf shape

Opposite below and alternate above, ovate to lance-shaped 10–25 cm, thick, rough and sandpapery on both sides, on coarse hairy stems.

Root system

A shallow mat of fibrous roots with rhizomes running out from the crown and swelling into tubers at their tips, mostly in the top 25 cm. Every fragment left in the ground regrows, which is the whole reason for the containment warning — a bed is effectively permanent once planted.

Fruit description

Not a fruit crop. The small sunflower heads set little viable seed in cool summers, and the crop is entirely the tuber: knobbly, thin-skinned, white to pink or purple, 5–10 cm, sweet and nutty from inulin rather than starch.

Propagation

Plant whole tubers or pieces with a bud, 10–15 cm deep, in early spring — exactly as for potatoes. Seed is irrelevant in practice.

Pollination

Self-fertile

The edible parts listed above are a starting point, not a field guide. Identify a plant with certainty — ideally against a local authority — before eating any part of it, and read the full disclaimer. Spotted something wrong? Report it.