Greenly Garden

Brussels: frost dates

Belgium

In Brussels the last spring frost usually comes around 10 April and the first autumn frost around 22 November, which leaves about 226 frost-free days (median of 2016–2025). Tomato seedlings can go into open ground around 16 May.

Last spring frostaround 10 April
First autumn frostaround 22 November
Frost-free days226 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

CropSow for seedlingsPlant out in a greenhouseOpen ground
Achocha15 February27 March17 April
Arugula—27 Februarysow 20 March
Basil10 April18 May8 June
Beet—27 Februarysow 20 March
Bell Pepper5 March18 May8 June
Black-eyed Susan14 February—17 April
Bok Choy20 February27 March17 April
Broad bean—27 Februarysow 20 March
Broccoli—27 Februarysow 20 March
Brussels Sprouts13 January27 February20 March
Cabbage—27 Februarysow 20 March
Calendula—27 Februarysow 20 March
Carrot——sow 20 March
Cauliflower16 January27 February20 March
Celeriac9 January27 March17 April
Celery9 January27 March17 April
Celosia12 March26 April17 May
Chamomile—27 Februarysow 20 March
Chayote1 January30 March20 April
Chickpea——sow 20 March
Chili Pepper17 March30 May20 June
China aster27 March18 May8 June
Chives——sow 20 March
Cilantro—27 Februarysow 20 March
Corn—30 Marchsow 20 April
Cosmos12 March26 April17 May
Cucumber6 April18 May8 June
Daikon—27 Februarysow 20 March
Delphinium20 January—20 March
Dill—27 Februarysow 20 March
Eggplant9 March18 May8 June
Florence fennel10 February27 March17 April
Garden sorrel—27 Februarysow 20 March
Green Beans21 February30 March20 April
Hyssop——sow 20 March
Kale—27 Februarysow 20 March
Kiwano24 March25 April16 May
Kohlrabi—27 Februarysow 20 March
Leek19 December27 February20 March
Lemon balm—27 Februarysow 20 March
Lettuce—27 Februarysow 20 March
Lisianthus2 December27 February20 March
Lovage——sow 20 March
Luffa6 April18 May8 June
Marigold13 February27 March17 April
Melon27 March18 May8 June
Microgreens—26 Aprilsow 17 May
Moringa5 April30 May20 June
Mustard greens—27 Februarysow 20 March
Napa cabbage22 February27 March17 April
Nasturtium17 February27 March17 April
Okra6 April18 May8 June
Oregano29 December27 February20 March
Pansy2 January27 February20 March
Parsley—27 Februarysow 20 March
Parsnip——sow 20 March
Peanut11 April18 May8 June
Peas—27 Februarysow 20 March
Petunia16 March18 May8 June
Physalis11 March25 April16 May
Pumpkin19 March25 April16 May
Purple coneflower17 January—20 March
Radish——sow 20 March
Sage9 January27 February20 March
Snapdragon24 December27 February20 March
Spinach—27 Februarysow 20 March
Stevia7 March25 April16 May
Stock—27 Februarysow 20 March
Sunflower—26 Aprilsow 17 May
Sweet Corn—30 Marchsow 20 April
Sweet pea16 January27 February20 March
Sweet William——sow 20 March
Swiss Chard—27 Februarysow 20 March
Thyme—27 Februarysow 20 March
Tomato27 February25 April16 May
Turnip—27 Februarysow 20 March
Watercress—27 Februarysow 20 March
Watermelon16 April18 May8 June
Zinnia25 April30 May20 June
Zucchini24 March25 April16 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.

Planted in autumn

CropPlant around
Bearded Iris23 October
Crocus23 October
Daffodil23 October
Garlic23 October
Hyacinth23 October
Lily23 October
Peony23 October
Saffron23 October
Tulip23 October
Wild garlic23 October

A month before the first autumn frost, so the roots grow before winter.