Gardening in South Korea: climate, frost dates and crops by region

Climate zones of South Korea

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

How the regions of South Korea differ

Splitting the cities in two — north (Chuncheon, Gangneung, Seoul and 2 more) and south (Jeonju, Ulsan, Busan and 2 more): the last spring frost comes about 7 days later in the north; the frost-free season is about 225 days in the north and 239 days in the south; the north gets about 1,254 mm of rain a year and the south about 1,521 mm.

The gap between the warmest month’s days and the coldest month’s nights is widest in Seoul (36.6 °C) and smallest in Jeju City (26.7 °C): the smaller it is, the milder both winter and summer. Jeju City is the wettest of these cities with 2,020 mm a year, Daejeon the driest with 1,224 mm. The hottest summer days are in Daegu (31 °C on average in the warmest month), the coolest in Gangneung (28.4 °C). In 9 of the 10 cities at least one month averages below 0 °C at night; the longest such winter is in Chuncheon (December–March).

Which crops suit which part of South Korea

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.

Cities of South Korea: weather in numbers

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

More about South Korea

• South Korea: frost dates by city
• Where to buy seeds and plants
• When to plant tomatoes in South Korea
• When to plant cucumbers in South Korea
• When to plant peas in South Korea
• When to plant garlic in South Korea
• Gardening by country