GreenlyLondon: frost dates
United Kingdom
In London the last spring frost usually comes around 4 April and the first autumn frost around 23 November, which leaves about 233 frost-free days (median of 2016–2025). Tomato seedlings can go into open ground around 24 May.
| Last spring frost | around 4 April |
|---|---|
| First autumn frost | around 23 November |
| Frost-free days | 233 days |
Median of 2016–2025 for the 25 km grid cell of the city: the last day at or below 0 °C in spring and the first in autumn (ERA5 reanalysis via Open-Meteo). In a cold year a frost can come a week or two later — Greenly warns 48 hours ahead.
When to sow and plant
| Crop | Sow for seedlings | Plant out in a greenhouse | Open ground |
|---|---|---|---|
| Achocha | 14 February | 26 March | 16 April |
| Arugula | — | 21 February | sow 14 March |
| Basil | 14 April | 22 May | 12 June |
| Beet | — | 21 February | sow 14 March |
| Bell Pepper | 9 March | 22 May | 12 June |
| Black-eyed Susan | 13 February | — | 16 April |
| Bok Choy | 19 February | 26 March | 16 April |
| Broad bean | — | 21 February | sow 14 March |
| Broccoli | — | 21 February | sow 14 March |
| Brussels Sprouts | 7 January | 21 February | 14 March |
| Cabbage | — | 21 February | sow 14 March |
| Calendula | — | 21 February | sow 14 March |
| Carrot | — | — | sow 14 March |
| Cauliflower | 10 January | 21 February | 14 March |
| Celeriac | 8 January | 26 March | 16 April |
| Celery | 8 January | 26 March | 16 April |
| Celosia | 22 March | 6 May | 27 May |
| Chamomile | — | 21 February | sow 14 March |
| Chayote | 2 January | 31 March | 21 April |
| Chickpea | — | — | sow 14 March |
| Chili Pepper | 25 March | 7 June | 28 June |
| China aster | 31 March | 22 May | 12 June |
| Chives | — | — | sow 14 March |
| Cilantro | — | 21 February | sow 14 March |
| Corn | — | 31 March | sow 21 April |
| Cosmos | 22 March | 6 May | 27 May |
| Cucumber | 10 April | 22 May | 12 June |
| Daikon | — | 21 February | sow 14 March |
| Delphinium | 14 January | — | 14 March |
| Dill | — | 21 February | sow 14 March |
| Eggplant | 13 March | 22 May | 12 June |
| Florence fennel | 9 February | 26 March | 16 April |
| Garden sorrel | — | 21 February | sow 14 March |
| Green Beans | 22 February | 31 March | 21 April |
| Hyssop | — | — | sow 14 March |
| Kale | — | 21 February | sow 14 March |
| Kiwano | 1 April | 3 May | 24 May |
| Kohlrabi | — | 21 February | sow 14 March |
| Leek | 13 December | 21 February | 14 March |
| Lemon balm | — | 21 February | sow 14 March |
| Lettuce | — | 21 February | sow 14 March |
| Lisianthus | 26 November | 21 February | 14 March |
| Lovage | — | — | sow 14 March |
| Luffa | 10 April | 22 May | 12 June |
| Marigold | 12 February | 26 March | 16 April |
| Melon | 31 March | 22 May | 12 June |
| Microgreens | — | 6 May | sow 27 May |
| Moringa | 13 April | 7 June | 28 June |
| Mustard greens | — | 21 February | sow 14 March |
| Napa cabbage | 21 February | 26 March | 16 April |
| Nasturtium | 16 February | 26 March | 16 April |
| Okra | 10 April | 22 May | 12 June |
| Oregano | 23 December | 21 February | 14 March |
| Pansy | 27 December | 21 February | 14 March |
| Parsley | — | 21 February | sow 14 March |
| Parsnip | — | — | sow 14 March |
| Peanut | 15 April | 22 May | 12 June |
| Peas | — | 21 February | sow 14 March |
| Petunia | 20 March | 22 May | 12 June |
| Physalis | 19 March | 3 May | 24 May |
| Pumpkin | 27 March | 3 May | 24 May |
| Purple coneflower | 11 January | — | 14 March |
| Radish | — | — | sow 14 March |
| Sage | 3 January | 21 February | 14 March |
| Snapdragon | 18 December | 21 February | 14 March |
| Spinach | — | 21 February | sow 14 March |
| Stevia | 15 March | 3 May | 24 May |
| Stock | — | 21 February | sow 14 March |
| Sunflower | — | 6 May | sow 27 May |
| Sweet Corn | — | 31 March | sow 21 April |
| Sweet pea | 10 January | 21 February | 14 March |
| Sweet William | — | — | sow 14 March |
| Swiss Chard | — | 21 February | sow 14 March |
| Thyme | — | 21 February | sow 14 March |
| Tomato | 7 March | 3 May | 24 May |
| Turnip | — | 21 February | sow 14 March |
| Watercress | — | 21 February | sow 14 March |
| Watermelon | 20 April | 22 May | 12 June |
| Zinnia | 3 May | 7 June | 28 June |
| Zucchini | 1 April | 3 May | 24 May |
Planting out: a week after the last frost once the soil is warm enough for the crop; frost-hardy crops three weeks before it; an unheated greenhouse three weeks earlier. Seedlings are sown so they are ready on that day.
London: weather for the next 7 days
Forecast by Open-Meteo. Nights at or below 0 °C are marked as frost.
Weather in London by month
Average weather in London over 2016–2025: the warmest month is July, the wettest October.
| Month | Day, °C | Night, °C | Rain, mm | Rainy days |
|---|---|---|---|---|
| January | 7.7 | 1.9 | 63 | 12 |
| February | 9.3 | 3 | 55 | 11 |
| March | 11.2 | 4 | 60 | 14 |
| April | 14.2 | 5.1 | 41 | 9 |
| May | 17.8 | 8.7 | 54 | 11 |
| June | 21.3 | 12.1 | 60 | 11 |
| July | 22.9 | 14.2 | 60 | 11 |
| August | 22.6 | 13.9 | 52 | 10 |
| September | 19.8 | 11.7 | 64 | 11 |
| October | 15.5 | 9 | 80 | 13 |
| November | 10.9 | 5.3 | 71 | 12 |
| December | 9 | 4 | 69 | 12 |
Average of the daily highs and lows, rain per month and days with at least 1 mm (ERA5 via Open-Meteo, the same grid cell as the frost dates).
Planted in autumn
| Crop | Plant around |
|---|---|
| Bearded Iris | 24 October |
| Crocus | 24 October |
| Daffodil | 24 October |
| Garlic | 24 October |
| Hyacinth | 24 October |
| Lily | 24 October |
| Peony | 24 October |
| Saffron | 24 October |
| Tulip | 24 October |
| Wild garlic | 24 October |
A month before the first autumn frost, so the roots grow before winter.