When to plant zucchini in Ulsan: 18 May – 30 August

In Ulsan, zucchini: sow for seedlings from 6 April to 9 August; plant into a greenhouse from 27 April to 30 August; plant out into open ground from 18 May to 30 August.

Zucchini in Ulsan: soil, season and weather

In Ulsan the soil, not frost, sets the date: the last frost is over around 22 March, but the top 7 cm of soil reaches 18 °C — the minimum on the zucchini card — only around 18 May, 57 days later.

Last spring frost	22 March
Top 7 cm of soil at 18 °C	18 May, 57 days after the last frost
First autumn frost	16 November, 182 days after the start
Days in the bed to the first harvest (card)	36
First harvest, if planted in this window	23 June – 5 October
Days left for picking	146
Daylight	13:29 on 27 April, 14:06 on 18 May
Watering outdoors when fruiting (card)	every 3 days; the driest month, November, has 4 rainy days

The same dates in Ulsan hold for Cucumber, Bell Pepper, Eggplant, Pumpkin and Watermelon.

Zucchini in Ulsan: care after planting

Planted on 18 May: in the first weeks water every 4 days.

Pests and diseases of zucchini to watch for:

Weather in Ulsan during the zucchini season

About 1199 mm of rain falls in the season; November is the driest month (37 mm) and September the wettest (268 mm).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
May	22.6	12.5	112	9	14:02
June	25.9	17.4	180	11	14:33
July	28.9	22.3	266	16	14:21
August	29.7	22.9	216	16	13:32
September	25	18.6	268	16	12:26
October	20	11.8	120	9	11:20
November	14.7	4.3	37	4	10:19

ERA5 2016–2025, Open-Meteo

Zucchini in nearby cities

Around Ulsan, Busan is 3 days earlier and Jeonju 1 day later.

City	Distance	Date	Difference
Busan	47 km	15 May – 5 September	3 days earlier
Daegu	74 km	16 May – 4 September	2 days earlier
Daejeon	195 km	17 May – 26 August	1 day earlier
Jeonju	198 km	19 May – 31 August	1 day later
Gwangju	228 km	17 May – 6 September	1 day earlier
Kitakyushu	234 km	from 15 May	3 days earlier

Where to buy zucchini plants and seeds near Ulsan

Buy plants ready to set out from 18 May to 30 August (from 27 April to 30 August for an unheated greenhouse); seed for raising your own is sown from 6 April to 9 August. Within 15 km of Ulsan OpenStreetMap lists 1 garden centre, 8 markets and 1 farm shop (collected 28 October 2026).

야음번개시장 — market
4 km
대송농수산물시장상가 — market
11 km
신울산시장 — market
2 km
울산원예농협 — farm shop
7 km

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.

Questions