When to sow sweet corn
In zone 8, most of the UK: sow direct from May to June. First harvest about 90 days later.
Growing stages
Sweet corn: 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 | Harvest | Harvest | Harvest | ||||||
| Zone 7 | Sowing or planting | Sowing or planting | Harvest | Harvest | Harvest | Harvest | ||||||
| Zone 8reference | Sowing or planting | Sowing or planting | Harvest | Harvest | Harvest | Harvest | ||||||
| Zone 9 | Sowing or planting | Sowing or planting | Sowing or planting, Harvest | Harvest | Harvest | Harvest | Harvest | |||||
| Zone 10 | Sowing or planting | Sowing or planting | Sowing or planting, Harvest | Harvest | Harvest | Harvest | 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.
Sweet corn in practice
- Spacing
- 30 cm along the row, 40 cm between rows
- Sun
- full sun
- Watering
- moderate
- Difficulty
- moderate
- In a pot
- no
- Support
- none
- Family
- Grasses (Poaceae)
- Watch for
- birds
Good companions for sweet corn
Keep apart
Questions about sweet corn
When to sow sweet corn?
In zone 8: sow direct from May to June. 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 90 days after sowing in zone 8, then the harvest lasts about 15 days.
How far apart?
30 cm between plants along the row and 40 cm between rows.
Can you grow sweet corn in a pot?
Open ground is better: the crop needs room and depth that a pot does not give.
What to plant nearby?
Good companions: dwarf bean, climbing bean, melon, red kuri squash, winter squash and courgette. Keep apart: cherry tomato and tomato.
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.