In the UK, sow summer radishes outdoors from March through August (a first cloche-protected sowing from late February in mild areas), with roots ready in just 3–6 weeks. Sow winter types such as mooli in July–August for harvest October–December.
Last updated 5 July 2026
Succession sowing guide, best varieties, and regional timing for radishes in UK gardens and allotments.
This page is a quick timing reference for exact sowing and harvest dates. For growing technique, spacing, care and troubleshooting, see our full How to Grow Radishes in the UK guide.
Ready to start growing? Read our full How to Grow Radishes UK →
Sowing dates and growing advice verified against RHS guidance by the SoilCommander Growing Team.
Radish Planting Calendar UK
| Task | Timing | Notes |
|---|---|---|
| First outdoor sow (under cloche) | Late Feb – March | Soil temp min 6°C; cloche or fleece recommended |
| Main outdoor sowing season | March – August | Sow every 2 weeks for continuous harvest |
| Winter radish sow | July – August | Mooli/daikon types; harvest October–December |
| Harvest (summer types) | April – October | Ready in 3–6 weeks; harvest promptly before they bolt |
🗺️ Regional timing: In southern England sow from early March (February under cloches) through to late September. In northern England start mid-to-late March and finish summer sowings by early September. In Scotland, sow April to August — and lean on spring and late-summer sowings, which bolt far less than midsummer ones.
Key Tips
- Succession sow every 2 weeks — radishes mature in 3–6 weeks and deteriorate fast if left in the ground
- Avoid sowing in midsummer heat — high temperatures cause bolting; resume in August for autumn crop
- Harvest promptly — don't wait for them to get bigger; they become woody and hot
- Great companion for carrots — germinates first to mark the row and break soil
Common Mistakes to Avoid
- Growing summer varieties for a late-season crop. Switch to mooli/daikon winter types sown July–August instead of continuing summer varieties into autumn.
- Letting the soil dry out in hot weather. The RHS notes dry conditions combined with heat cause roots to fail to swell.
- Sowing too thickly without thinning. Radishes need at least 2.5cm between plants for roots to swell properly — overcrowded rows produce all leaf and little root.
Frequently Asked Questions
When should I grow radishes in the UK?
Sow radishes every 2–3 weeks from March to September in the UK. Spring and early autumn sowings give the best quality — midsummer heat makes roots bolt and turn unpleasantly hot. In mild areas you can start in February under cloches.
What is the best radish variety for UK gardens?
'Scarlet Globe' AGM is quick-maturing with a mild flavour when young; 'French Breakfast 4 Francis' AGM has crunchy, mildly peppery flesh; 'Amethyst' AGM is slower to turn woody than most. For full technique on growing each type, see How to Grow Radishes UK.
Why do my radishes bolt (flower) instead of forming a root?
Hot, dry weather is the main trigger. Keep plants well watered through summer and remove any that start to send up a flower stem.
How much space do radishes need?
At least 2.5cm between salad varieties — overcrowding is a common reason roots fail to swell properly.
Plan Your Radish Sowings
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