Greenly Garden
Get the app
EN

Last and first frost dates in Osaka

Japan

In Osaka the last spring frost usually comes around 14 March and the first autumn frost around 17 December, which leaves about 278 frost-free days (median of 2016–2025). Tomato seedlings can go into open ground from 15 April to 27 August.

Last spring frostaround 14 March
First autumn frostaround 17 December
Frost-free days278 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 Osaka?

The last frost in Osaka usually comes around 14 March: 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 21 February, while corn waits until 29 March. The first autumn frost follows around 17 December, about 278 days later: harvest or cover frost-tender crops before then.

When to sow and plant

CropSow for seedlingsPlant out in a greenhouseOpen ground
Achocha19 January – 8 September28 February – 18 October21 March – 18 October
Ageratumfrom 28 January—from 15 April
Arugula——sow 21 February – 12 November
Basil7 March – 15 October14 April – 22 November5 May – 22 November
Beet——sow 21 February – 18 October
Bell Pepper13 February – 28 June14 April – 27 August5 May – 27 August
Black-eyed Susanfrom 28 December—from 21 March
Bok Choy24 January – 26 October28 February – 30 November21 March – 30 November
Borage——sow 21 March – 23 October
Broad bean——sow 21 February – 8 September
Broccoli——sow 21 February – 1 September
Brussels Sprouts17 December – 30 July31 January – 13 September21 February – 13 September
Busy Lizziefrom 27 December—from 21 March
Cabbage——sow 21 February – 9 August
Calendula——sow from 21 February
Carrot——sow 21 February – 24 September
Cauliflower20 December – 1 September31 January – 13 October21 February – 13 October
Celeriac13 December – 29 June28 February – 14 September21 March – 14 September
Celery13 December – 9 July28 February – 24 September21 March – 24 September
Celosiafrom 14 Februaryfrom 31 Marchfrom 21 April
Chamomile——sow 21 February – 13 October
Chayote10 December – 22 June8 March – 18 September29 March – 18 September
Chickpea——sow 21 February – 29 August
Chicory6 January – 23 September—21 February – 18 October
Chili Pepper13 February – 4 August14 April – 3 October5 May – 3 October
China asterfrom 21 Februaryfrom 14 Aprilfrom 5 May
Chives——sow 21 February – 4 October
Cilantro——sow 21 February – 14 October
Corn——sow 29 March – 29 August
Corn poppy——sow from 21 February
Cosmosfrom 14 Februaryfrom 31 Marchfrom 21 April
Cucumber17 March – 4 September14 April – 2 October5 May – 2 October
Daikon——sow 21 February – 11 October
Delphiniumfrom 3 December—from 21 February
Dill——sow 21 February – 24 October
Edging lobeliafrom 27 December—from 21 March
Eggplant13 February – 28 June14 April – 27 August5 May – 27 August
Florence fennel14 January – 8 September28 February – 23 October21 March – 23 October
Foxglovefrom 15 November—from 21 February
Garden sorrel——sow 21 February – 12 October
Green Beans——sow 21 April – 6 September
Hollyhock——sow from 21 February
Hyssop——sow 21 February – 4 September
Kale——sow 21 February – 6 October
Kiwano21 February – 11 September25 March – 13 October15 April – 13 October
Kohlrabi——sow 21 February – 16 October
Leek22 November – 20 June31 January – 29 August21 February – 29 August
Lemon balm——sow 21 February – 8 October
Lettuce——sow 21 February – 21 October
Lisianthusfrom 5 Novemberfrom 31 Januaryfrom 21 February
Lovage——sow from 21 February
Luffa3 March – 6 July14 April – 17 August5 May – 17 August
Marigoldfrom 17 Januaryfrom 28 Februaryfrom 21 March
Marjoram13 February – 23 September—5 May – 22 November
Melon17 March – 22 August14 April – 19 September5 May – 19 September
Microgreens——sow 21 April – 3 December
Moringa3 March – 28 September27 April – 22 November18 May – 22 November
Moss rosefrom 3 January—from 21 March
Mustard greens——sow 21 February – 2 November
Napa cabbage26 January – 3 October28 February – 5 November21 March – 5 November
Nasturtiumfrom 21 Januaryfrom 28 Februaryfrom 21 March
Okra3 March – 16 September14 April – 28 October5 May – 28 October
Oregano2 December – 13 September31 January – 12 November21 February – 12 November
Pansyfrom 6 Decemberfrom 31 Januaryfrom 21 February
Parsley——sow 21 February – 2 October
Parsnip——sow 21 February – 21 August
Peanut8 March – 12 August14 April – 18 September5 May – 18 September
Peas——sow 21 February – 4 October
Petuniafrom 10 Februaryfrom 14 Aprilfrom 5 May
Physalis8 February – 9 August25 March – 23 September15 April – 23 September
Pumpkin3 March – 11 July14 April – 22 August5 May – 22 August
Purple coneflowerfrom 30 November—from 21 February
Radish——sow 21 February – 17 November
Sage13 December – 9 September31 January – 28 October21 February – 28 October
Scarlet sagefrom 1 February—from 15 April
Snapdragonfrom 27 Novemberfrom 31 Januaryfrom 21 February
Soybean——sow 5 May – 28 September
Spinach——sow 21 February – 23 October
Stevia4 February – 31 July25 March – 18 September15 April – 18 September
Stock——sow from 21 February
Sunflower——sow from 21 April
Sweet alyssum——sow from 21 February
Sweet Corn18 February – 23 September12 March – 15 October2 April – 15 October
Sweet peafrom 20 Decemberfrom 31 Januaryfrom 21 February
Sweet William——sow from 21 February
Swiss Chard——sow 21 February – 18 October
Thyme——sow 21 February – 29 August
Tomato1 February – 6 July25 March – 27 August15 April – 27 August
Turnip——sow 21 February – 20 October
Watercress——sow 21 February – 31 October
Watermelon17 March – 10 August14 April – 7 September5 May – 7 September
Zinniafrom 23 Marchfrom 27 Aprilfrom 18 May
Zucchini24 March – 9 September14 April – 30 September5 May – 30 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 Osaka

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 1 day after the last spring frost and 15 °C 32 days after it.

SoilDateAgainst the last spring frost
5 °C16 January57 days earlier
10 °C15 March1 day later
15 °C15 April32 days later
18 °C5 May52 days later

Frost dates near Osaka

Of the nearest cities on our list, the last spring frost ends earliest in Hamamatsu (24 February) and latest in Hiroshima (9 April).

CityDistanceLast spring frostFirst autumn frost
Kyoto43 km22 March7 December
Nagoya139 km22 March10 December
Okayama145 km20 March15 December
Hamamatsu204 km24 February18 December
Hiroshima281 km9 April25 November

Seeds, seedlings and markets in Osaka

Within 15 km of Osaka OpenStreetMap lists 16 garden centres, 4 farm-supply shops, 3 plant nurseries, 19 markets and 8 farm shops (collected 28 October 2026). The nearest garden centre to the city centre is 花しきぶ, 13 km away.

Places: © OpenStreetMap contributors, ODbL.

What to grow at home in winter in Osaka

Frosts in Osaka usually come from about 17 December to about 14 March. 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 Osaka by month

Average weather in Osaka over 2016–2025: the warmest month is August. Months that average 20 °C or more by day: May–October (22.5–32.5 °C). Months that average 30 °C or more by day: July (30.8 °C) and August (32.5 °C). No month averages below 0 °C at night; the coldest nights, in January, average 0.6 °C. About 1729 mm of rain falls in a year, on 125 days; June is the wettest month (244 mm) and January the driest (47 mm).

MonthDay, °CNight, °CRain, mmRainy days
January8.70.6476
February9.51.1628
March13.74.910810
April18.79.814810
May2314.518910
June26.519.124414
July30.823.924015
August32.525.117314
September28.921.720914
October22.514.718811
November16.88.3727
December11.12.8496

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 17 November
Crocus17 November – end of December
Daffodil17 November – end of December
Garlic17 November – end of December
Grape hyacinthby 17 November
Helleboreby 17 November
Hyacinth17 November – end of December
Lilyby 17 November
Ornamental onionby 17 November
Peonyby 17 November
Saffronby 17 November
Snowdropby 17 November
Tulip17 November – end of December
Wild garlicby 17 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).