When to sow radishes
In zone 8, most of the UK: sow direct from March to September. First harvest about 30 days later.
Growing stages
Radishes: calendar by hardiness zone
| Zone | January | February | March | April | May | June | July | August | September | October | November | December |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Zone 6 | Sowing or planting | Sowing or planting, Harvest | Sowing or planting, Harvest | Sowing or planting, Harvest | Sowing or planting, Harvest | Harvest | Harvest | |||||
| Zone 7 | Sowing or planting, Harvest | Sowing or planting, Harvest | Sowing or planting, Harvest | Sowing or planting, Harvest | Sowing or planting, Harvest | Sowing or planting, Harvest | Sowing or planting, Harvest | Harvest | Harvest | |||
| Zone 8reference | Sowing or planting, Harvest | Sowing or planting, Harvest | Sowing or planting, Harvest | Sowing or planting, Harvest | Sowing or planting, Harvest | Sowing or planting, Harvest | Sowing or planting, Harvest | Harvest | Harvest | |||
| Zone 9 | Sowing or planting | Sowing or planting, Harvest | Sowing or planting, Harvest | Sowing or planting, Harvest | Harvest | Harvest | Sowing or planting | Sowing or planting, Harvest | Harvest | Harvest | ||
| Zone 10 | Sowing or planting, Harvest | Sowing or planting, Harvest | Sowing or planting, Harvest | Sowing or planting, Harvest | Harvest | Harvest | Sowing or planting | Sowing or planting, Harvest | Sowing or planting, Harvest | Sowing or planting, Harvest |
- Zone 6
- −23 to −18 °C (−10 to 0 °F): high mountains
- Zone 7
- −18 to −12 °C (0 to 10 °F): upland Britain, eastern France, the Alps
- Zone 8
- −12 to −7 °C (10 to 20 °F): most of the UK and France
- Zone 9
- −7 to −1 °C (20 to 30 °F): south-west England, Brittany, Atlantic and Mediterranean coasts
- Zone 10
- −1 to 4 °C (30 to 40 °F): Isles of Scilly, the French Riviera, coastal Corsica
Indicative months. A cold year or a garden at altitude shifts everything by a month; watch the frosts too.
Radishes in practice
- Spacing
- 5 cm along the row, 15 cm between rows
- Sun
- copes with part shade
- Watering
- moderate
- Difficulty
- easy
- In a pot
- yes
- Support
- none
- Family
- Brassicas (Brassicaceae)
Good companions for radishes
Keep apart
none noted
Questions about radishes
When to sow radishes?
In zone 8: sow direct from March to September. The four other zones are in the calendar above; at altitude or after a long winter, aim for the end of the window.
How long until harvest?
About 30 days after sowing in zone 8, then the harvest lasts about 10 days.
How far apart?
5 cm between plants along the row and 15 cm between rows.
Can you grow radishes in a pot?
Yes, in a deep enough pot, in the sun shown above. Soil dries fast in a pot: watch the watering more than in the ground.
What to plant nearby?
Good companions: dwarf bean, carrot, cucumber, lettuce, melon, pea, spinach and courgette. Keep apart: none noted.
Updated 20 October 2026, Hortipix catalogue version 1. Windows still being checked against Le Guide Clause, Vilmorin and Terre vivante (RHS and Cornell for the UK and the US), compared with OpenFarm (CC0). They remain indicative.