How to grow Jerusalem artichoke

Helianthus tuberosus · sunchoke

A hardy perennial sunflower grown for its knobbly edible tubers, dug from late autumn through winter. Tall plants up to 3 m bear small yellow sunflower-like flowers in late summer and autumn.

Quick facts

Type	Vegetable
Family	Asteraceae
Light	Full sun
Soil pH	5.8–7
Frost	tolerates light frost
Soil for sowing	from 7 °C
Germination	14 days
Sowing to harvest	210 days
Where it grows	Open ground

When to plant

It tolerates light frost: sow straight into the bed about three weeks before your last spring frost.

The first harvest comes about 210 days after the shoots appear.

Frost dates · When to plant

Care

Open ground

Stage	Watering	Temperature	Feeding
Germination	—	—	—
Growth	every 7 days	18…27 °C	balanced (NPK), 30 days into the stage; balanced (NPK), 60 days into the stage
Flowering	every 7 days	18…27 °C	balanced (NPK), at the start of the stage
Harvest	—	—	—

Growing notes

Light

Best in full sun; it still crops in partial shade, but the harvest is smaller.

Soil

Moderately fertile, moisture-retentive but well-drained soil; adapts to a wide pH range, about pH 5.8–7. Heavy, waterlogged clay rots the tubers and lowers yields.

Care

Plant tubers the size of a hen's egg 10–15 cm deep and 30–60 cm apart in early spring. Water during dry spells, especially from late summer when the tubers swell, and earth up the stems to 15 cm when they are 30 cm tall. Stake or shorten tall stems to 1.5 m in windy sites. Dig the tubers from late autumn, after the foliage dies back; they keep best in the ground, frost is said to improve the flavour, and any tuber left behind will sprout next year.

Pests and diseases of Jerusalem artichoke

White mould (Sclerotinia)

Sources

Figures checked against these sources.