Gardening in Portugal: climate, frost dates and crops by region

We worked out the season of 23 cities of Portugal from ten years of weather: the frost-free season lasts from 233 days in Bragança to 343 days in Castelo Branco. The last spring frost comes first in Évora (around 12 January) and last in Bragança (around 7 April). 8 of the cities had no frost at all.

Climate zones of Portugal

By the days between the last spring frost and the first autumn frost.

Zone	Cities	Frost-free days	Last spring frost	First autumn frost
270 frost-free days or more	Viana do Castelo, Braga, Guimarães, Vila Real, Porto, Viseu, Castelo Branco, Beja	300 – 343	17 January – 13 February	10 December – 28 December
210–269 frost-free days	Bragança, Guarda	233 – 237	2 April – 7 April	25 November – 26 November
Frost without a regular season	Póvoa de Varzim, Coimbra, Leiria, Santarém, Évora	—	12 January – 29 January	—
No frost in ten years	Aveiro, Sintra, Lisbon, Setúbal, Ponta Delgada, Portimão, Faro, Funchal	—	—	—

How the regions of Portugal differ

Splitting the cities in two — north (Bragança, Viana do Castelo, Braga and 8 more) and south (Leiria, Santarém, Sintra and 8 more): the last spring frost comes about 13 days later in the north; the north gets about 1,192 mm of rain a year and the south about 641 mm.

Splitting the cities in two — west (Porto, Aveiro, Santarém and 8 more) and east (Bragança, Guarda, Castelo Branco and 8 more): the last spring frost comes about 11 days later in the east; the warmest month averages 25.2 °C by day in the west and 29.6 °C in the east; the west gets about 1,018 mm of rain a year and the east about 819 mm.

The gap between the warmest month’s days and the coldest month’s nights is widest in Castelo Branco (30.1 °C) and smallest in Ponta Delgada (12.2 °C): the smaller it is, the milder both winter and summer. Viana do Castelo is the wettest of these cities with 1,961 mm a year, Faro the driest with 474 mm. The hottest summer days are in Castelo Branco (35.1 °C on average in the warmest month), the coolest in Funchal (21.8 °C). In none of these cities does a month average below 0 °C at night.

Which crops suit which part of Portugal

Season long enough: the days from planting to the first autumn frost cover the days to the first harvest on the plant card. 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.

Crop	Planting out or sowing	Season long enough	Tight or too short
Tomato	21 March (Beja) – 7 September (Beja)	all 15	—
Cucumber	17 April (Beja) – 13 October (Beja)	all 15	—
Bell Pepper, Eggplant	17 April (Beja) – 7 September (Beja)	all 15	—
Zucchini	17 April (Beja) – 11 October (Beja)	all 15	—
Pumpkin	17 April (Beja) – 2 September (Beja)	all 15	—
Watermelon	17 April (Beja) – 18 September (Beja)	all 15	—
Peas	27 December (Castelo Branco) – 15 October (Beja)	all 15	—
Garlic, Tulip, Daffodil, Crocus, Hyacinth	Autumn planting: 26 October (Guarda) – end of December (Bragança)	—	—

Cities without a spring frost: months that suit each crop

Months whose average day is not above the highest temperature on the plant card and whose average night is not below its lowest.

City	Tomato	Cucumber	Bell Pepper	Eggplant	Watermelon
Aveiro	July, August	none	June–September	none	none
Sintra	June–September	none	June–October	none	none
Lisbon	June and September	August	June–October	none	August
Setúbal	June and September	August	June–October	none	August
Ponta Delgada	June–November	July–October	May–November	none	July–October
Portimão	none	July, August	June and September, October	none	July, August
Faro	June and September, October	July–September	May–October	none	July–September
Funchal	none	none	none	none	none

Cities of Portugal: weather in numbers

City	Frost-free days	Warmest month, day	Coldest month, night	Rain a year	Driest month	Places to buy
Bragança	233	August, 29 °C	January, 0.7 °C	819 mm	August	3
Viana do Castelo	312	August, 24.8 °C	January, 4.3 °C	1,961 mm	July	5
Braga	332	August, 27.9 °C	January, 5.1 °C	1,611 mm	July	30
Guimarães	300	August, 28.3 °C	January, 4.6 °C	1,815 mm	August	—
Póvoa de Varzim	—	August, 24.9 °C	January, 6.6 °C	1,563 mm	July	—
Vila Real	336	August, 31.4 °C	January, 4 °C	1,053 mm	July	37
Porto	327	August, 27.4 °C	January, 6.2 °C	1,599 mm	August	41
Viseu	306	August, 30 °C	January, 3.7 °C	1,158 mm	July	11
Aveiro	no frost	July, 23.2 °C	January, 7.5 °C	1,192 mm	August	21
Guarda	237	August, 28.4 °C	January, 1 °C	771 mm	August	2
Coimbra	—	August, 29.3 °C	January, 6.2 °C	1,063 mm	August	16
Castelo Branco	343	August, 35.1 °C	January, 5 °C	695 mm	August	5
Leiria	—	August, 27.7 °C	January, 6.4 °C	896 mm	August	16
Santarém	—	August, 30.9 °C	January, 6.8 °C	641 mm	August	11
Sintra	no frost	August, 22.5 °C	January, 10.1 °C	734 mm	August	—
Lisbon	no frost	August, 28.7 °C	January, 8.8 °C	650 mm	July	46
Évora	—	August, 33.3 °C	January, 6.4 °C	632 mm	August	8
Setúbal	no frost	August, 29.1 °C	January, 8.8 °C	608 mm	August	22
Beja	325	August, 35 °C	January, 5.8 °C	482 mm	July	6
Ponta Delgada	no frost	August, 25.2 °C	February, 13 °C	1,315 mm	July	7
Portimão	no frost	August, 32.6 °C	January, 8.2 °C	502 mm	July	—
Faro	no frost	August, 29.6 °C	January, 9.5 °C	474 mm	August	16
Funchal	no frost	August, 21.8 °C	February, 5.8 °C	1,018 mm	July	24

ERA5 2016–2025 via Open-Meteo, 25 km grid cell of each city; dates by the Greenly calendar and the plant cards.