Last and first frost dates in La Rioja

When is the last frost in La Rioja?

The last frost in La Rioja usually comes around 17 July: 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 26 June, while corn waits until 24 July. The first autumn frost follows around 15 June, about 333 days later: harvest or cover frost-tender crops before then.

When to sow and plant

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 La Rioja

The day the top 7 cm of soil first averages each temperature over a week, median of 2016–2025 (ERA5 via Open-Meteo).

Frost dates near La Rioja

Of the nearest cities on our list, the last spring frost ends earliest in San Fernando del Valle de Catamarca (15 July) and latest in Córdoba (5 August).

Seeds, seedlings and markets in La Rioja

Within 15 km of La Rioja OpenStreetMap lists 2 markets (collected 28 October 2026). The nearest market to the city centre is El Gato Negro, 1 km away.

• El Gato Negro — market
  Lamadrid 401, 5300 La Rioja · 1 km

• Where to buy seeds and seedlings in La Rioja
• Selling your own harvest in Argentina

Places: © OpenStreetMap contributors, ODbL.

Weather in La Rioja by month

Average weather in La Rioja over 2016–2025: the warmest month is January. Months that average 20 °C or more by day: August–May (20.6–34.7 °C). Months that average 30 °C or more by day: November–March (30.1–34.7 °C). No month averages below 0 °C at night; the coldest nights, in July, average 6.5 °C. About 526 mm of rain falls in a year, on 56 days; January is the wettest month (130 mm) and July the driest (4 mm).

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

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).