In the garden now (2 November 2026)
Belfast planting calendar
Bars show when each crop can go in and when a planting from that window is ready. The blue band is the frost season, from the average first autumn frost to the average last spring frost. Hover or tap a crop for details.
Sow indoorsSow or plant outdoorsHarvestFrost seasonToday
Swipe sideways to see the whole year →
Dates by crop
| Crop | Sow indoors | Sow / plant outdoors | Harvest |
|---|---|---|---|
| Tomato | No outdoor window passes all the checks here; grow it under cover or try a specialist variety. | ||
| Pepper | Summers are too cool for a reliable outdoor crop. Grow it in a greenhouse or polytunnel. | ||
| Eggplant (aubergine) | Summers are too cool for a reliable outdoor crop. Grow it in a greenhouse or polytunnel. | ||
| Cucumber | No outdoor window passes all the checks here; grow it under cover or try a specialist variety. | ||
| Zucchini (courgette) | May 23 – Jun 10 | Jun 20 – Jul 1 sow | Sep 2 – Oct 1 |
| Pumpkin and winter squash | No outdoor window passes all the checks here; grow it under cover or try a specialist variety. | ||
| Watermelon | Summers are too cool for a reliable outdoor crop. Grow it in a greenhouse or polytunnel. | ||
| Sweet corn | No outdoor window passes all the checks here; grow it under cover or try a specialist variety. | ||
| Green beans | – | Jun 20 – Jun 24 sow | Sep 12 – Oct 1 |
| Peas | – | Mar 7 – Aug 15 sow | Jun 23 – Nov 14 |
| Lettuce | Feb 10 – Mar 10 | Mar 17 – Aug 30 sow | Jun 10 – Nov 17 |
| Spinach | – | Mar 3 – Sep 8 sow | Jun 1 – Dec 7 |
| Kale | Jan 27 – Mar 3 | Mar 10 – Aug 25 sow | Jun 18 – Dec 22 |
| Cabbage | Feb 2 – Mar 9 | Mar 23 – Aug 9 plant out | Jul 6 – Nov 28 |
| Broccoli | Feb 3 – Mar 10 | Mar 24 – Aug 17 plant out | Jun 27 – Nov 21 |
| Carrots | – | Mar 24 – Aug 15 sow | Jul 1 – Dec 22 |
| Beets (beetroot) | – | Mar 24 – Aug 22 sow | Jun 22 – Nov 28 |
| Radishes | – | Mar 13 – Sep 25 sow | May 13 – Nov 21 |
| Onions | Jan 6 – Feb 10 | Mar 17 – Jul 13 plant out | Jul 26 – Nov 7 |
| Garlic | – | Sep 12 – Oct 16 sow | Jun 19 – Jul 9 |
| Potatoes | – | Apr 5 – Jul 18 sow | Jul 27 – Nov 7 |
| Swiss chard | – | Apr 5 – Aug 27 sow | Jun 21 – Nov 28 |
| Basil | Summers are too cool for a reliable outdoor crop. Grow it in a greenhouse or polytunnel. | ||
| Cilantro (coriander) | – | Mar 24 – Sep 10 sow | Jun 1 – Nov 21 |
| Parsley | Feb 8 – Mar 15 | Apr 5 – Aug 10 sow | Jul 10 – Dec 7 |
Dates are for a typical year and the middle of the window is the safest. Sow a little at a time across a window rather than all at once. Cold snaps, heat waves, frost pockets and city warmth all shift the real dates; watch the forecast.
Frost dates in Belfast
- Average last spring frost
- April 14
- Late frost (1 year in 10)
- April 30 approx.
- Average first autumn frost
- November 7
- Early frost (1 year in 10)
- October 24 approx.
- Frost-free growing season
- 206 days
“Average” is the date with an even chance of a later (spring) or earlier (autumn) frost: a night at or below 0 °C (32 °F) at screen height. Tender crops go out a week or two after the spring date, which brings the risk down to about one year in ten.
Source: Estimated from TerraClimate 1991–2020 climate normals (typical error about a week; how).
Climate at a glance
- Hardiness zone
- 9a estimate
- Average coldest winter night
- -6°C22°F
- Warmest month
- July, highs 21°C69°F
- Coldest month
- January, lows 2°C35°F
- Crops with an outdoor window
- 17 of 25
The zone follows the USDA scheme: bands of the average lowest temperature of the year, 10 °F wide, split into a and b halves. Estimated from monthly climate normals; about one city in ten we checked comes out a full half-zone off. It tells you which perennials survive winter, not when to sow.
Temperature and rain by month
Average highAverage lowRainFreezing point
| Month | High | Low | Mean | Rain |
|---|---|---|---|---|
| January | 7°C45°F | 2°C35°F | 4°C40°F | 73 mm2.9 in |
| February | 8°C47°F | 2°C35°F | 5°C41°F | 59 mm2.3 in |
| March | 11°C51°F | 3°C38°F | 7°C44°F | 58 mm2.3 in |
| April | 13°C56°F | 5°C41°F | 9°C48°F | 57 mm2.2 in |
| May | 17°C62°F | 7°C45°F | 12°C54°F | 58 mm2.3 in |
| June | 19°C67°F | 10°C51°F | 15°C59°F | 68 mm2.7 in |
| July | 21°C69°F | 12°C54°F | 16°C62°F | 73 mm2.9 in |
| August | 20°C68°F | 12°C53°F | 16°C61°F | 83 mm3.3 in |
| September | 18°C64°F | 10°C49°F | 14°C56°F | 73 mm2.9 in |
| October | 14°C56°F | 7°C45°F | 10°C51°F | 86 mm3.4 in |
| November | 10°C50°F | 4°C39°F | 7°C45°F | 85 mm3.3 in |
| December | 7°C45°F | 2°C36°F | 5°C40°F | 78 mm3.1 in |
Monthly averages 1991–2020 from TerraClimate (about 4 km grid).