Greenly Garden

Last and first frost dates in Guimarães

Portugal

In Guimarães the last spring frost usually comes around 13 February and the first autumn frost around 10 December, which leaves about 300 frost-free days (median of 2016–2025). Tomato seedlings can go into open ground from 22 April to 20 August.

Last spring frostaround 13 February
First autumn frostaround 10 December
Frost-free days300 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 Guimarães?

The last frost in Guimarães usually comes around 13 February: 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 23 January, while corn waits until 21 March. The first autumn frost follows around 10 December, about 300 days later: harvest or cover frost-tender crops before then.

When to sow and plant

CropSow for seedlingsPlant out in a greenhouseOpen ground
Achocha21 December – 1 September30 January – 11 October20 February – 11 October
Ageratumfrom 4 February—from 22 April
Arugula——sow 23 January – 5 November
Basil27 March – 8 October4 May – 15 November25 May – 15 November
Beet——sow 23 January – 11 October
Bell Pepper5 March – 21 June4 May – 20 August25 May – 20 August
Black-eyed Susanfrom 29 November—from 20 February
Bok Choy26 December – 19 October30 January – 23 November20 February – 23 November
Borage——sow 20 February – 16 October
Broad bean——sow 23 January – 1 September
Broccoli——sow 23 January – 25 August
Brussels Sprouts18 November – 23 July2 January – 6 September23 January – 6 September
Busy Lizziefrom 28 November—from 20 February
Cabbage——sow 23 January – 2 August
Calendula——sow from 23 January
Carrot——sow 23 January – 17 September
Cauliflower21 November – 25 August2 January – 6 October23 January – 6 October
Celeriac14 November – 22 June30 January – 7 September20 February – 7 September
Celery14 November – 2 July30 January – 17 September20 February – 17 September
Celosiafrom 28 Februaryfrom 14 Aprilfrom 5 May
Chamomile——sow 23 January – 6 October
Chayote2 December – 15 June28 February – 11 September21 March – 11 September
Chickpea——sow 23 January – 22 August
Chicory8 December – 16 September—23 January – 11 October
Chili Pepper5 March – 28 July4 May – 26 September25 May – 26 September
China asterfrom 13 Marchfrom 4 Mayfrom 25 May
Chives——sow 23 January – 27 September
Cilantro——sow 23 January – 7 October
Corn——sow 21 March – 22 August
Corn poppy——sow from 23 January
Cosmosfrom 28 Februaryfrom 14 Aprilfrom 5 May
Cucumber6 April – 28 August4 May – 25 September25 May – 25 September
Daikon——sow 23 January – 4 October
Delphiniumfrom 4 November—from 23 January
Dill——sow 23 January – 17 October
Edging lobeliafrom 28 November—from 20 February
Eggplant5 March – 21 June4 May – 20 August25 May – 20 August
Florence fennel16 December – 1 September30 January – 16 October20 February – 16 October
Foxglovefrom 17 October—from 23 January
Garden sorrel——sow 23 January – 5 October
Green Beans——sow 5 May – 30 August
Hollyhock——sow from 23 January
Hyssop——sow 23 January – 28 August
Kale——sow 23 January – 29 September
Kiwano28 February – 4 September1 April – 6 October22 April – 6 October
Kohlrabi——sow 23 January – 9 October
Leek24 October – 13 June2 January – 22 August23 January – 22 August
Lemon balm——sow 23 January – 1 October
Lettuce——sow 23 January – 14 October
Lisianthusfrom 7 Octoberfrom 2 Januaryfrom 23 January
Lovage——sow from 23 January
Luffa23 March – 29 June4 May – 10 August25 May – 10 August
Marigoldfrom 19 Decemberfrom 30 Januaryfrom 20 February
Marjoram5 March – 16 September—25 May – 15 November
Melon6 April – 15 August4 May – 12 September25 May – 12 September
Microgreens——sow 5 May – 26 November
Moringa16 March – 21 September10 May – 15 November31 May – 15 November
Moss rosefrom 5 December—from 20 February
Mustard greens——sow 23 January – 26 October
Napa cabbage28 December – 26 September30 January – 29 October20 February – 29 October
Nasturtiumfrom 23 Decemberfrom 30 Januaryfrom 20 February
Okra23 March – 9 September4 May – 21 October25 May – 21 October
Oregano3 November – 6 September2 January – 5 November23 January – 5 November
Pansyfrom 7 Novemberfrom 2 Januaryfrom 23 January
Parsley——sow 23 January – 25 September
Parsnip——sow 23 January – 14 August
Peanut28 March – 5 August4 May – 11 September25 May – 11 September
Peas——sow 23 January – 27 September
Petuniafrom 2 Marchfrom 4 Mayfrom 25 May
Physalis15 February – 2 August1 April – 16 September22 April – 16 September
Pumpkin23 March – 4 July4 May – 15 August25 May – 15 August
Purple coneflowerfrom 1 November—from 23 January
Radish——sow 23 January – 10 November
Sage14 November – 2 September2 January – 21 October23 January – 21 October
Scarlet sagefrom 8 February—from 22 April
Snapdragonfrom 29 Octoberfrom 2 Januaryfrom 23 January
Soybean——sow 25 May – 21 September
Spinach——sow 23 January – 16 October
Stevia11 February – 24 July1 April – 11 September22 April – 11 September
Stock——sow from 23 January
Sunflower——sow from 5 May
Sweet alyssum——sow from 23 January
Sweet Corn16 February – 16 September10 March – 8 October31 March – 8 October
Sweet peafrom 21 Novemberfrom 2 Januaryfrom 23 January
Sweet William——sow from 23 January
Swiss Chard——sow 23 January – 11 October
Thyme——sow 23 January – 22 August
Tomato8 February – 29 June1 April – 20 August22 April – 20 August
Turnip——sow 23 January – 13 October
Watercress——sow 23 January – 24 October
Watermelon6 April – 3 August4 May – 31 August25 May – 31 August
Zinniafrom 5 Aprilfrom 10 Mayfrom 31 May
Zucchini13 April – 2 September4 May – 23 September25 May – 23 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 Guimarães

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 18 days before the last spring frost and 15 °C 68 days after it.

SoilDateAgainst the last spring frost
5 °Calready in the first week of January—
10 °C26 January18 days earlier
15 °C22 April68 days later
18 °C25 May101 days later

Frost dates near Guimarães

Of the nearest cities on our list, the last spring frost ends earliest in Póvoa de Varzim (19 January) and latest in Viana do Castelo (3 February).

CityDistanceLast spring frostFirst autumn frost
Braga16 km25 January23 December
Póvoa de Varzim39 km19 January—
Porto41 km26 January19 December
Vila Real49 km20 January22 December
Viana do Castelo52 km3 February12 December

What to grow at home in winter in Guimarães

Frosts in Guimarães usually come from about 10 December to about 13 February. 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 Guimarães by month

Average weather in Guimarães over 2016–2025: the warmest month is August. Months that average 20 °C or more by day: May–October (20.8–28.3 °C). No month averages below 0 °C at night; the coldest nights, in January, average 4.6 °C. About 1815 mm of rain falls in a year, on 131 days; November is the wettest month (242 mm) and August the driest (19 mm).

MonthDay, °CNight, °CRain, mmRainy days
January12.44.624113
February14.15.617011
March15.16.119714
April17.88.217713
May20.910.811612
June23.613.58310
July27.615.8204
August28.316.2193
September24.614788
October20.811.923513
November15.3824215
December13.26.123715

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 10 November
Crocusby 10 November
Daffodilby 10 November
Garlic10 November – end of December
Grape hyacinthby 10 November
Helleboreby 10 November
Hyacinthby 10 November
Lilyby 10 November
Ornamental onionby 10 November
Peonyby 10 November
Saffronby 10 November
Snowdropby 10 November
Tulipby 10 November
Wild garlicby 10 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).