Rhubarb
Garden Rhubarb, Pie Plant, Wine Plant
Hardy perennial for zones 3–8. Do not harvest stalks at all in year 1; harvest lightly in year 2. From year 3, harvest by pulling/twisting stalks rather than cutting, and leave at least 2/3 of the plant's stalks. Caution: leaves are toxic (high oxalic acid) — harvest stalks only. Needs winter cold for dormancy; does not thrive in warm climates. Divide crowns every 5–8 years. Mulch generously in winter.
- Germination
- 14–21 days
- Spacing
- 90–120 cm
When to plant rhubarb
Plant 2–6 weeks before your last spring frost.
Dashed line: typical last spring frost in zone 7 (Apr 5). Zone dates are averages; most of the UK is zone 8–9, central Europe 6–7 and the Baltics and Scandinavia 4–6. In the app, Tomatograph uses your garden's own frost dates.
How to grow rhubarb
- 1
Plant crowns
Plant divisions in early spring as soon as the soil can be worked, with each bud just below the surface. Rhubarb needs a cold winter to do well.
- 2
Be patient
Don't pull any stalks in the first year and only a few in the second.
- 3
Look after it
Mulch generously each winter and divide crowns every 5–8 years. Remove flower stalks as they appear.
- 4
Harvest
From year three, twist and pull stalks rather than cutting, leaving at least a third of them. Only the stalks are edible; the leaves are toxic.
Growing conditions
Light
Full sun
Water
Medium water
Temperature
-30–27 °C
Frost tolerance
Frost-hardy — tolerates frost
Days to maturity
365–730 days
How Tomatograph watches your rhubarb
Tomatograph checks your local forecast every morning and only speaks up when one of these applies to your garden.
- First frost within 14 daysReminder to mulch the roots before winter.
- 3 days at 35 °C or aboveHeat-wave alert while plants are flowering or fruiting: shade and water early.
- Humidity above 80% for 48 hoursCheck for crown rot, which thrives in those conditions.
- Within a week of maturityHarvest-window reminder based on when you planted.
Rhubarb questions
- When should I plant rhubarb?
- Plant 2–6 weeks before your last spring frost.
- How far apart should I plant rhubarb?
- Allow 90–120 cm between plants.
- What grows well with rhubarb?
- Good neighbours include strawberry, onion, garlic.
Growing guide written by Tomatograph. Planting figures from openplantdb (CC0 1.0). Zone frost dates are averages from openplantdb (CC0 1.0).