Greenly

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
Bell Pepper5 March18 May8 June
Chili Pepper17 March30 May20 June
Corn—30 Marchsow 20 April
Cucumber6 April18 May8 June
Eggplant9 March18 May8 June
Green Beans21 February30 March20 April
Melon27 March18 May8 June
Peas—27 Februarysow 20 March
Physalis11 March25 April16 May
Pumpkin19 March25 April16 May
Sweet Corn—30 Marchsow 20 April
Tomato27 February25 April16 May
Watermelon16 April18 May8 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
Crocus23 October
Daffodil23 October
Garlic23 October
Hyacinth23 October
Lily23 October
Tulip23 October

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