Greenly Garden

Last and first frost dates in Amersfoort

Netherlands

In Amersfoort the last spring frost usually comes around 10 April and the first autumn frost around 21 November, which leaves about 225 frost-free days (median of 2016–2025). Tomato seedlings can go into open ground from 13 May to 1 August.

Last spring frostaround 10 April
First autumn frostaround 21 November
Frost-free days225 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 Amersfoort?

The last frost in Amersfoort usually comes around 10 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 20 March, while corn waits until 22 April. The first autumn frost follows around 21 November, about 225 days later: harvest or cover frost-tender crops before then.

When to sow and plant

CropSow for seedlingsPlant out in a greenhouseOpen ground
Achocha15 February – 13 August27 March – 22 September17 April – 22 September
Ageratumfrom 25 February—from 13 May
Arugula——sow 20 March – 17 October
Basil8 April – 19 September16 May – 27 October6 June – 27 October
Beet——sow 20 March – 22 September
Bell Pepper17 March – 2 June16 May – 1 August6 June – 1 August
Black-eyed Susanfrom 24 January—from 17 April
Bok Choy20 February – 30 September27 March – 4 November17 April – 4 November
Borage——sow 17 April – 27 September
Broad bean——sow 20 March – 13 August
Broccoli——sow 20 March – 6 August
Brussels Sprouts13 January – 4 July27 February – 18 August20 March – 18 August
Busy Lizziefrom 23 January—from 17 April
Cabbage——sow 20 March – 14 July
Calendula——sow from 20 March
Carrot——sow 20 March – 29 August
Cauliflower16 January – 6 August27 February – 17 September20 March – 17 September
Celeriac9 January – 3 June27 March – 19 August17 April – 19 August
Celery9 January – 13 June27 March – 29 August17 April – 29 August
Celosiafrom 10 Marchfrom 24 Aprilfrom 15 May
Chamomile——sow 20 March – 17 September
Chayote3 January – 27 May1 April – 23 August22 April – 23 August
Chickpea——sow 20 March – 3 August
Chicory2 February – 28 August—20 March – 22 September
Chili Pepper17 March – 9 July16 May – 7 September6 June – 7 September
China asterfrom 25 Marchfrom 16 Mayfrom 6 June
Chives——sow 20 March – 8 September
Cilantro——sow 20 March – 18 September
Corn——sow 22 April – 3 August
Corn poppy——sow from 20 March
Cosmosfrom 10 Marchfrom 24 Aprilfrom 15 May
Cucumber18 April – 9 August16 May – 6 September6 June – 6 September
Daikon——sow 20 March – 15 September
Delphiniumfrom 30 December—from 20 March
Dill——sow 20 March – 28 September
Edging lobeliafrom 23 January—from 17 April
Eggplant17 March – 2 June16 May – 1 August6 June – 1 August
Florence fennel10 February – 13 August27 March – 27 September17 April – 27 September
Foxglovefrom 12 December—from 20 March
Garden sorrel——sow 20 March – 16 September
Green Beans——sow 15 May – 11 August
Hollyhock——sow from 20 March
Hyssop——sow 20 March – 9 August
Kale——sow 20 March – 10 September
Kiwano21 March – 16 August22 April – 17 September13 May – 17 September
Kohlrabi——sow 20 March – 20 September
Leek19 December – 25 May27 February – 3 August20 March – 3 August
Lemon balm——sow 20 March – 12 September
Lettuce——sow 20 March – 25 September
Lisianthusfrom 2 Decemberfrom 27 Februaryfrom 20 March
Lovage——sow from 20 March
Luffa4 April – 10 June16 May – 22 July6 June – 22 July
Marigoldfrom 13 Februaryfrom 27 Marchfrom 17 April
Marjoram17 March – 28 August—6 June – 27 October
Melon18 April – 27 July16 May – 24 August6 June – 24 August
Microgreens——sow 15 May – 7 November
Moringa7 April – 2 September1 June – 27 October22 June – 27 October
Moss rosefrom 30 January—from 17 April
Mustard greens——sow 20 March – 7 October
Napa cabbage22 February – 7 September27 March – 10 October17 April – 10 October
Nasturtiumfrom 17 Februaryfrom 27 Marchfrom 17 April
Okra4 April – 21 August16 May – 2 October6 June – 2 October
Oregano29 December – 18 August27 February – 17 October20 March – 17 October
Pansyfrom 2 Januaryfrom 27 Februaryfrom 20 March
Parsley——sow 20 March – 6 September
Parsnip——sow 20 March – 26 July
Peanut9 April – 17 July16 May – 23 August6 June – 23 August
Peas——sow 20 March – 8 September
Petuniafrom 14 Marchfrom 16 Mayfrom 6 June
Physalis8 March – 14 July22 April – 28 August13 May – 28 August
Pumpkin4 April – 15 June16 May – 27 July6 June – 27 July
Purple coneflowerfrom 27 December—from 20 March
Radish——sow 20 March – 22 October
Sage9 January – 14 August27 February – 2 October20 March – 2 October
Scarlet sagefrom 1 March—from 13 May
Snapdragonfrom 24 Decemberfrom 27 Februaryfrom 20 March
Soybean——sow 6 June – 2 September
Spinach——sow 20 March – 27 September
Stevia4 March – 5 July22 April – 23 August13 May – 23 August
Stock——sow from 20 March
Sunflower——sow from 15 May
Sweet alyssum——sow from 20 March
Sweet Corn22 March – 28 August13 April – 19 September4 May – 19 September
Sweet peafrom 16 Januaryfrom 27 Februaryfrom 20 March
Sweet William——sow from 20 March
Swiss Chard——sow 20 March – 22 September
Thyme——sow 20 March – 3 August
Tomato1 March – 10 June22 April – 1 August13 May – 1 August
Turnip——sow 20 March – 24 September
Watercress——sow 20 March – 5 October
Watermelon18 April – 15 July16 May – 12 August6 June – 12 August
Zinniafrom 27 Aprilfrom 1 Junefrom 22 June
Zucchini25 April – 14 August16 May – 4 September6 June – 4 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 Amersfoort

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 3 days after the last spring frost and 15 °C 33 days after it.

SoilDateAgainst the last spring frost
5 °Calready in the first week of January—
10 °C13 April3 days later
15 °C13 May33 days later
18 °C6 June57 days later

Frost dates near Amersfoort

Of the nearest cities on our list, the last spring frost ends earliest in Haarlem (19 March) and latest in Almere (15 April).

CityDistanceLast spring frostFirst autumn frost
Utrecht20 km27 March23 November
Almere26 km15 April21 November
Amsterdam41 km3 April21 November
Haarlem57 km19 March30 November
Tilburg70 km10 April22 November

What to grow at home in winter in Amersfoort

Frosts in Amersfoort usually come from about 21 November to about 10 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 Amersfoort by month

Average weather in Amersfoort over 2016–2025: the warmest month is August. Months that average 20 °C or more by day: June (21.9 °C), July (22.4 °C) and August (22.8 °C). No month averages below 0 °C at night; the coldest nights, in January, average 1.5 °C. About 900 mm of rain falls in a year, on 158 days; October is the wettest month (93 mm) and April the driest (62 mm).

MonthDay, °CNight, °CRain, mmRainy days
January6.41.57915
February8.11.98013
March10.72.76313
April144.86212
May18.48.66812
June21.912.67613
July22.413.78314
August22.8147213
September19.811.57711
October15.399315
November9.94.47213
December7.52.97514

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 22 October
Crocus22 October – end of December
Daffodil22 October – end of December
Garlic22 October – end of December
Grape hyacinthby 22 October
Helleboreby 22 October
Hyacinth22 October – end of December
Lilyby 22 October
Ornamental onionby 22 October
Peonyby 22 October
Saffronby 22 October
Snowdropby 22 October
Tulip22 October – end of December
Wild garlicby 22 October

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).