Greenly Garden

Last and first frost dates in Ostend

Belgium

In Ostend the last spring frost usually comes around 3 April and the first autumn frost around 1 December, which leaves about 242 frost-free days (median of 2016–2025). Tomato seedlings can go into open ground from 20 May to 11 August.

Last spring frostaround 3 April
First autumn frostaround 1 December
Frost-free days242 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 is the last frost in Ostend?

The last frost in Ostend usually comes around 3 April: that is the median of 2016–2025, so in about half of those years the last night at or below 0 °C came later. Hardy crops start before it and frost-tender ones only after it: in the table below arugula can go into open ground from 13 March, while corn waits until 26 April. The first autumn frost follows around 1 December, about 242 days later: harvest or cover frost-tender crops before then.

When to sow and plant

CropSow for seedlingsPlant out in a greenhouseOpen ground
Achocha8 February – 23 August20 March – 2 October10 April – 2 October
Ageratumfrom 4 March—from 20 May
Arugula——sow 13 March – 27 October
Basil19 April – 29 September27 May – 6 November17 June – 6 November
Beet——sow 13 March – 2 October
Bell Pepper28 March – 12 June27 May – 11 August17 June – 11 August
Black-eyed Susanfrom 17 January—from 10 April
Bok Choy13 February – 10 October20 March – 14 November10 April – 14 November
Borage——sow 10 April – 7 October
Broad bean——sow 13 March – 23 August
Broccoli——sow 13 March – 16 August
Brussels Sprouts6 January – 14 July20 February – 28 August13 March – 28 August
Busy Lizziefrom 16 January—from 10 April
Cabbage——sow 13 March – 24 July
Calendula——sow from 13 March
Carrot——sow 13 March – 8 September
Cauliflower9 January – 16 August20 February – 27 September13 March – 27 September
Celeriac2 January – 13 June20 March – 29 August10 April – 29 August
Celery2 January – 23 June20 March – 8 September10 April – 8 September
Celosiafrom 21 Marchfrom 5 Mayfrom 26 May
Chamomile——sow 13 March – 27 September
Chayote7 January – 6 June5 April – 2 September26 April – 2 September
Chickpea——sow 13 March – 13 August
Chicory26 January – 7 September—13 March – 2 October
Chili Pepper28 March – 19 July27 May – 17 September17 June – 17 September
China asterfrom 5 Aprilfrom 27 Mayfrom 17 June
Chives——sow 13 March – 18 September
Cilantro——sow 13 March – 28 September
Corn——sow 26 April – 13 August
Corn poppy——sow from 13 March
Cosmosfrom 21 Marchfrom 5 Mayfrom 26 May
Cucumber29 April – 19 August27 May – 16 September17 June – 16 September
Daikon——sow 13 March – 25 September
Delphiniumfrom 23 December—from 13 March
Dill——sow 13 March – 8 October
Edging lobeliafrom 16 January—from 10 April
Eggplant28 March – 12 June27 May – 11 August17 June – 11 August
Florence fennel3 February – 23 August20 March – 7 October10 April – 7 October
Foxglovefrom 5 December—from 13 March
Garden sorrel——sow 13 March – 26 September
Green Beans——sow 26 May – 21 August
Hollyhock——sow from 13 March
Hyssop——sow 13 March – 19 August
Kale——sow 13 March – 20 September
Kiwano28 March – 26 August29 April – 27 September20 May – 27 September
Kohlrabi——sow 13 March – 30 September
Leek12 December – 4 June20 February – 13 August13 March – 13 August
Lemon balm——sow 13 March – 22 September
Lettuce——sow 13 March – 5 October
Lisianthusfrom 25 Novemberfrom 20 Februaryfrom 13 March
Lovage——sow from 13 March
Luffa15 April – 20 June27 May – 1 August17 June – 1 August
Marigoldfrom 6 Februaryfrom 20 Marchfrom 10 April
Marjoram28 March – 7 September—17 June – 6 November
Melon29 April – 6 August27 May – 3 September17 June – 3 September
Microgreens——sow 26 May – 17 November
Moringa17 April – 12 September11 June – 6 November2 July – 6 November
Moss rosefrom 23 January—from 10 April
Mustard greens——sow 13 March – 17 October
Napa cabbage15 February – 17 September20 March – 20 October10 April – 20 October
Nasturtiumfrom 10 Februaryfrom 20 Marchfrom 10 April
Okra15 April – 31 August27 May – 12 October17 June – 12 October
Oregano22 December – 28 August20 February – 27 October13 March – 27 October
Pansyfrom 26 Decemberfrom 20 Februaryfrom 13 March
Parsley——sow 13 March – 16 September
Parsnip——sow 13 March – 5 August
Peanut20 April – 27 July27 May – 2 September17 June – 2 September
Peas——sow 13 March – 18 September
Petuniafrom 25 Marchfrom 27 Mayfrom 17 June
Physalis15 March – 24 July29 April – 7 September20 May – 7 September
Pumpkin15 April – 25 June27 May – 6 August17 June – 6 August
Purple coneflowerfrom 20 December—from 13 March
Radish——sow 13 March – 1 November
Sage2 January – 24 August20 February – 12 October13 March – 12 October
Scarlet sagefrom 8 March—from 20 May
Snapdragonfrom 17 Decemberfrom 20 Februaryfrom 13 March
Soybean——sow 17 June – 12 September
Spinach——sow 13 March – 7 October
Stevia11 March – 15 July29 April – 2 September20 May – 2 September
Stock——sow from 13 March
Sunflower——sow from 26 May
Sweet alyssum——sow from 13 March
Sweet Corn17 March – 7 September8 April – 29 September29 April – 29 September
Sweet peafrom 9 Januaryfrom 20 Februaryfrom 13 March
Sweet William——sow from 13 March
Swiss Chard——sow 13 March – 2 October
Thyme——sow 13 March – 13 August
Tomato8 March – 20 June29 April – 11 August20 May – 11 August
Turnip——sow 13 March – 4 October
Watercress——sow 13 March – 15 October
Watermelon29 April – 25 July27 May – 22 August17 June – 22 August
Zinniafrom 7 Mayfrom 11 Junefrom 2 July
Zucchini6 May – 24 August27 May – 14 September17 June – 14 September

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. Each window starts on the Greenly calendar date and ends on the last day that still leaves the crop’s days to harvest (from its card) before the average first autumn frost, plus six weeks of picking for crops harvested over weeks (tomatoes, peppers, aubergines, cucumbers, courgettes, pumpkins, watermelons, beans) — our rule; earlier in the window is safer.

When the soil warms up in Ostend

The day the top 7 cm of soil first averages each temperature over a week, median of 2016–2025 (ERA5 via Open-Meteo). The soil reaches 10 °C 4 days after the last spring frost and 15 °C 47 days after it.

SoilDateAgainst the last spring frost
5 °Calready in the first week of January—
10 °C7 April4 days later
15 °C20 May47 days later
18 °C17 June75 days later

Frost dates near Ostend

Of the nearest cities on our list, the last spring frost ends earliest in Bruges (27 March) and latest in Ghent (12 April).

CityDistanceLast spring frostFirst autumn frost
Bruges20 km27 March30 November
Kortrijk49 km4 April22 November
Ghent58 km12 April24 November
Lille66 km8 April21 November
Aalst84 km10 April21 November

What to grow at home in winter in Ostend

Frosts in Ostend usually come from about 1 December to about 3 April. These plants have indoor care in their Greenly cards and are harvested quickly, so they can be sown on a windowsill in winter.

Weather in Ostend by month

Average weather in Ostend over 2016–2025: the warmest month is August. Months that average 20 °C or more by day: June (20.5 °C), July (21.8 °C) and August (22.2 °C). No month averages below 0 °C at night; the coldest nights, in January, average 2.3 °C. About 836 mm of rain falls in a year, on 153 days; November is the wettest month (88 mm) and April the driest (52 mm).

MonthDay, °CNight, °CRain, mmRainy days
January7.12.38415
February8.836013
March10.83.86913
April13.55.65211
May16.99.15511
June20.512.76611
July21.814.36212
August22.214.76912
September19.912.67112
October15.89.98213
November10.75.78816
December8.33.87814

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

CropWhen to plant
Bearded Irisby 1 November
Crocus1 November – end of December
Daffodil1 November – end of December
Garlic1 November – end of December
Grape hyacinthby 1 November
Helleboreby 1 November
Hyacinth1 November – end of December
Lilyby 1 November
Ornamental onionby 1 November
Peonyby 1 November
Saffronby 1 November
Snowdropby 1 November
Tulip1 November – end of December
Wild garlicby 1 November

From a month before the first autumn frost, so the roots grow before winter, to the late-planting limit on each crop’s page (about two weeks before the ground freezes, by ten years of weather).