When to plant zucchini in Okayama: 14 May – 28 September

In Okayama, zucchini: sow for seedlings from 2 April to 7 September; plant into a greenhouse from 23 April to 28 September; plant out into open ground from 14 May to 28 September.

Zucchini in Okayama: soil, season and weather

In Okayama the soil, not frost, sets the date: the last frost is over around 20 March, but the top 7 cm of soil reaches 18 °C — the minimum on the zucchini card — only around 14 May, 55 days later.

Last spring frost	20 March
Top 7 cm of soil at 18 °C	14 May, 55 days after the last frost
First autumn frost	15 December, 215 days after the start
Days in the bed to the first harvest (card)	36
First harvest, if planted in this window	19 June – 3 November
Days left for picking	179
Daylight	13:18 on 23 April, 13:56 on 14 May
Watering outdoors when fruiting (card)	every 3 days; the driest month, December, has 5 rainy days

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

Zucchini in Okayama: care after planting

Planted on 14 May: in the first weeks water every 4 days.

Pests and diseases of zucchini to watch for:

Weather in Okayama during the zucchini season

About 1132 mm of rain falls in the season; December is the driest month (37 mm) and July the wettest (230 mm).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
May	23.4	13.6	133	10	13:58
June	26.7	18.3	208	14	14:28
July	30.5	23.1	230	15	14:16
August	32.4	24.2	162	13	13:29
September	28.3	20.8	193	14	12:26
October	22.4	14.2	115	10	11:21
November	16.7	7.7	54	6	10:22
December	10.8	2.3	37	5	9:51

ERA5 2016–2025, Open-Meteo

Zucchini in nearby cities

Around Okayama, Osaka is 9 days earlier and Hiroshima 12 days later.

City	Distance	Date	Difference
Hiroshima	138 km	26 May – 8 September	12 days later
Osaka	145 km	5 May – 30 September	9 days earlier
Kyoto	174 km	14 May – 20 September	same day
Nagoya	278 km	6 May – 23 September	8 days earlier
Kitakyushu	292 km	from 15 May	1 day later
Fukuoka	345 km	5 May – 4 October	9 days earlier

Where to buy zucchini plants and seeds near Okayama

Buy plants ready to set out from 14 May to 28 September (from 23 April to 28 September for an unheated greenhouse); seed for raising your own is sown from 2 April to 7 September. Within 15 km of Okayama OpenStreetMap lists 8 garden centres, 5 farm-supply shops, 3 markets and 19 farm shops (collected 28 October 2026).

藤原農機商会 — farm supply
15 km
たねもの — farm supply
2 km
JA岡山鉾立資材店 — farm supply
13 km
岡山市中央卸売市場 — market
6 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