When to plant zucchini in Siena: 26 May – 10 September

In Siena, zucchini: sow for seedlings from 14 April to 20 August; plant into a greenhouse from 5 May to 10 September; plant out into open ground from 26 May to 10 September. For plants and seeds, the places nearby include Piante e Fiori l'Hibiscus (plant nursery, 2 km) and Brico & Garden (garden centre, 3 km); addresses and opening hours are below.

Zucchini in Siena: soil, season and weather

In Siena the soil, not frost, sets the date: the last frost is over around 16 March, but the top 7 cm of soil reaches 18 °C — the minimum on the zucchini card — only around 26 May, 71 days later.

Last spring frost	16 March
Top 7 cm of soil at 18 °C	26 May, 71 days after the last frost
First autumn frost	27 November, 185 days after the start
Days in the bed to the first harvest (card)	36
First harvest, if planted in this window	1 July – 16 October
Days left for picking	149
Daylight	14:17 on 5 May, 15:01 on 26 May
Watering outdoors when fruiting (card)	every 3 days; the driest month, July, has 4 rainy days

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

Zucchini in Siena: care after planting

Planted on 26 May: in the first weeks water every 4 days.

Pests and diseases of zucchini to watch for:

Weather in Siena during the zucchini season

About 470 mm of rain falls in the season; July is the driest month (22 mm) and November the wettest (107 mm).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
May	22.5	11	91	12	14:40
June	29.1	16	41	7	15:23
July	32.5	18.8	22	4	15:06
August	32.4	18.9	35	6	14:00
September	26.5	14.8	77	8	12:33
October	21.4	10.9	97	8	11:05
November	15.2	6.2	107	12	9:44

ERA5 2016–2025, Open-Meteo

Zucchini in nearby cities

Around Siena, Livorno is 10 days earlier and Pisa 21 days later.

City	Distance	Date	Difference
Arezzo	47 km	9 June – 4 September	14 days later
Florence	50 km	28 May – 10 September	2 days later
Livorno	84 km	from 16 May	10 days earlier
Pisa	87 km	16 June – 1 September	21 days later
Perugia	89 km	29 May – 8 September	3 days later
San Marino	113 km	16 May – 25 September	10 days earlier

Where to buy zucchini plants and seeds near Siena

Buy plants ready to set out from 26 May to 10 September (from 5 May to 10 September for an unheated greenhouse); seed for raising your own is sown from 14 April to 20 August. Within 15 km of Siena OpenStreetMap lists 3 garden centres, 2 farm-supply shops, 4 plant nurseries, 6 markets and 1 farm shop (collected 27 October 2026).

Mundi — garden centre
Viale Europa 51, 53100 Siena · 3 km · shop.mundi.it
Brico & Garden — garden centre
Via delle Arti 27, 53100 Siena · 3 km · bricook.it
Piante e Fiori l'Hibiscus — plant nursery
Strada Massetana Romana 7, 53100 Siena · 2 km
Sena Flora — plant nursery
Via Arno 2, 53018 Sovicille · 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