GreenlyHow to grow Rhubarb
Rheum × hybridum · pie plant
A long-lived perennial grown for its tart leaf stalks. It needs a cold winter (7–9 weeks below 3 °C) and grows best where summers are cool; growth stops above about 32 °C.
Quick facts
| Type | Vegetable |
|---|---|
| Family | Polygonaceae |
| Light | Full sun |
| Soil pH | 5.5–6.5 |
| Frost | tolerates light frost |
| Soil for sowing | from 5 °C |
| Germination | 14 days |
| Sowing to harvest | 400 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 400 days after the shoots appear.
Care
Open ground
| Stage | Watering | Temperature | Feeding |
|---|---|---|---|
| Growth | every 7 days | — | balanced (NPK), at the start of the stage |
| Flowering | every 7 days | — | — |
Growing notes
Light
Full sun. In hot summers some afternoon shade helps, but heavy shade gives thin stalks.
Soil
Any fertile, well-drained soil with plenty of well-rotted organic matter; pH 5.5–6.5 suits it. Waterlogged soil rots the crowns.
Care
Plant dormant crowns with the bud at or just below the surface, about 1 m apart. Water in dry spells, give a general fertiliser in spring just before the leaves appear (not in the first year) and mulch with well-rotted compost, keeping it off the crown. Remove flower stalks as soon as they appear. Do not harvest in the first season and only lightly in the second; then pull, do not cut, stalks 23–30 cm long, taking no more than half at a time. The leaves are poisonous — eat only the stalks.
Pests and diseases of Rhubarb
Sources
Figures checked against these sources.