Greenly Garden

Last and first frost dates in Daejeon

South Korea

In Daejeon the last spring frost usually comes around 1 April and the first autumn frost around 12 November, which leaves about 225 frost-free days (median of 2016–2025). Tomato seedlings can go into open ground from 24 April to 23 July.

Last spring frostaround 1 April
First autumn frostaround 12 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 Daejeon?

The last frost in Daejeon usually comes around 1 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 11 March, while corn waits until 10 April. The first autumn frost follows around 12 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
Achocha6 February – 4 August18 March – 13 September8 April – 13 September
Ageratumfrom 6 February—from 24 April
Arugula——sow 11 March – 8 October
Basil19 March – 10 September26 April – 18 October17 May – 18 October
Beet——sow 11 March – 13 September
Bell Pepper25 February – 24 May26 April – 23 July17 May – 23 July
Black-eyed Susanfrom 15 January—from 8 April
Bok Choy11 February – 21 September18 March – 26 October8 April – 26 October
Borage——sow 8 April – 18 September
Broad bean——sow 11 March – 4 August
Broccoli——sow 11 March – 28 July
Brussels Sprouts4 January – 25 June18 February – 9 August11 March – 9 August
Busy Lizziefrom 14 January—from 8 April
Cabbage——sow 11 March – 5 July
Calendula——sow from 11 March
Carrot——sow 11 March – 20 August
Cauliflower7 January – 28 July18 February – 8 September11 March – 8 September
Celeriac31 December – 25 May18 March – 10 August8 April – 10 August
Celery31 December – 4 June18 March – 20 August8 April – 20 August
Celosiafrom 26 Februaryfrom 12 Aprilfrom 3 May
Chamomile——sow 11 March – 8 September
Chayote22 December – 18 May20 March – 14 August10 April – 14 August
Chickpea——sow 11 March – 25 July
Chicory24 January – 19 August—11 March – 13 September
Chili Pepper25 February – 30 June26 April – 29 August17 May – 29 August
China asterfrom 5 Marchfrom 26 Aprilfrom 17 May
Chives——sow 11 March – 30 August
Cilantro——sow 11 March – 9 September
Corn——sow 10 April – 25 July
Corn poppy——sow from 11 March
Cosmosfrom 26 Februaryfrom 12 Aprilfrom 3 May
Cucumber29 March – 31 July26 April – 28 August17 May – 28 August
Daikon——sow 11 March – 6 September
Delphiniumfrom 21 December—from 11 March
Dill——sow 11 March – 19 September
Edging lobeliafrom 14 January—from 8 April
Eggplant25 February – 24 May26 April – 23 July17 May – 23 July
Florence fennel1 February – 4 August18 March – 18 September8 April – 18 September
Foxglovefrom 3 December—from 11 March
Garden sorrel——sow 11 March – 7 September
Green Beans——sow 3 May – 2 August
Hollyhock——sow from 11 March
Hyssop——sow 11 March – 31 July
Kale——sow 11 March – 1 September
Kiwano2 March – 7 August3 April – 8 September24 April – 8 September
Kohlrabi——sow 11 March – 11 September
Leek10 December – 16 May18 February – 25 July11 March – 25 July
Lemon balm——sow 11 March – 3 September
Lettuce——sow 11 March – 16 September
Lisianthusfrom 23 Novemberfrom 18 Februaryfrom 11 March
Lovage——sow from 11 March
Luffa15 March – 1 June26 April – 13 July17 May – 13 July
Marigoldfrom 4 Februaryfrom 18 Marchfrom 8 April
Marjoram25 February – 19 August—17 May – 18 October
Melon29 March – 18 July26 April – 15 August17 May – 15 August
Microgreens——sow 3 May – 29 October
Moringa20 March – 24 August14 May – 18 October4 June – 18 October
Moss rosefrom 21 January—from 8 April
Mustard greens——sow 11 March – 28 September
Napa cabbage13 February – 29 August18 March – 1 October8 April – 1 October
Nasturtiumfrom 8 Februaryfrom 18 Marchfrom 8 April
Okra15 March – 12 August26 April – 23 September17 May – 23 September
Oregano20 December – 9 August18 February – 8 October11 March – 8 October
Pansyfrom 24 Decemberfrom 18 Februaryfrom 11 March
Parsley——sow 11 March – 28 August
Parsnip——sow 11 March – 17 July
Peanut20 March – 8 July26 April – 14 August17 May – 14 August
Peas——sow 11 March – 30 August
Petuniafrom 22 Februaryfrom 26 Aprilfrom 17 May
Physalis17 February – 5 July3 April – 19 August24 April – 19 August
Pumpkin15 March – 6 June26 April – 18 July17 May – 18 July
Purple coneflowerfrom 18 December—from 11 March
Radish——sow 11 March – 13 October
Sage31 December – 5 August18 February – 23 September11 March – 23 September
Scarlet sagefrom 10 February—from 24 April
Snapdragonfrom 15 Decemberfrom 18 Februaryfrom 11 March
Soybean——sow 17 May – 24 August
Spinach——sow 11 March – 18 September
Stevia13 February – 26 June3 April – 14 August24 April – 14 August
Stock——sow from 11 March
Sunflower——sow from 3 May
Sweet alyssum——sow from 11 March
Sweet Corn5 March – 19 August27 March – 10 September17 April – 10 September
Sweet peafrom 7 Januaryfrom 18 Februaryfrom 11 March
Sweet William——sow from 11 March
Swiss Chard——sow 11 March – 13 September
Thyme——sow 11 March – 25 July
Tomato10 February – 1 June3 April – 23 July24 April – 23 July
Turnip——sow 11 March – 15 September
Watercress——sow 11 March – 26 September
Watermelon29 March – 6 July26 April – 3 August17 May – 3 August
Zinniafrom 9 Aprilfrom 14 Mayfrom 4 June
Zucchini5 April – 5 August26 April – 26 August17 May – 26 August

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 Daejeon

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 before the last spring frost and 15 °C 23 days after it.

SoilDateAgainst the last spring frost
5 °C8 March24 days earlier
10 °C29 March3 days earlier
15 °C24 April23 days later
18 °C17 May46 days later

Frost dates near Daejeon

Of the nearest cities on our list, the last spring frost ends earliest in Daegu (19 March) and latest in Chuncheon (6 April).

CityDistanceLast spring frostFirst autumn frost
Jeonju63 km27 March17 November
Daegu121 km19 March21 November
Seoul139 km29 March6 November
Gwangju140 km1 April23 November
Chuncheon172 km6 April31 October

Seeds, seedlings and markets in Daejeon

Within 15 km of Daejeon OpenStreetMap lists 24 markets and 1 farm shop (collected 28 October 2026). The nearest market to the city centre is 축산물도매시장, 2 km away.

Places: © OpenStreetMap contributors, ODbL.

What to grow at home in winter in Daejeon

Frosts in Daejeon usually come from about 12 November to about 1 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 Daejeon by month

Average weather in Daejeon over 2016–2025: the warmest month is August. Months that average 20 °C or more by day: May–September (23.2–30 °C). Months that average 30 °C or more by day: August (30 °C). Nights average below 0 °C in January (-5.1 °C), February (-3.6 °C) and December (-4 °C). About 1224 mm of rain falls in a year, on 107 days; July is the wettest month (265 mm) and January the driest (26 mm).

MonthDay, °CNight, °CRain, mmRainy days
January3-5.1265
February5.4-3.6355
March12.51.3537
April18.56.8737
May23.211.8899
June27.417.114511
July29.221.626517
August302221918
September25.217.216811
October18.79.8788
November12.12.4455
December4.3-4284

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 13 October
Crocus13 October – 5 December
Daffodil13 October – 5 December
Garlic13 October – 5 December
Grape hyacinthby 13 October
Helleboreby 13 October
Hyacinth13 October – 5 December
Lilyby 13 October
Ornamental onionby 13 October
Peonyby 13 October
Saffronby 13 October
Snowdropby 13 October
Tulip13 October – 5 December
Wild garlicby 13 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).