When to plant zucchini in Rennes: 1 June – 11 September

In Rennes, zucchini: sow for seedlings from 20 April to 21 August; plant into a greenhouse from 11 May to 11 September; plant out into open ground from 1 June to 11 September. For plants and seeds, the places nearby include Delourmel Agriculture (farm supply, 4 km) and Irvin (farm supply, 15 km); addresses and opening hours are below.

Zucchini in Rennes: soil, season and weather

In Rennes the soil, not frost, sets the date: the last frost is over around 12 March, but the top 7 cm of soil reaches 18 °C — the minimum on the zucchini card — only around 1 June, 81 days later.

Last spring frost	12 March
Top 7 cm of soil at 18 °C	1 June, 81 days after the last frost
First autumn frost	28 November, 180 days after the start
Days in the bed to the first harvest (card)	36
First harvest, if planted in this window	7 July – 17 October
Days left for picking	144
Daylight	14:59 on 11 May, 15:47 on 1 June
Watering outdoors when fruiting (card)	every 3 days; the driest month, August, has 9 rainy days

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

Zucchini in Rennes: care after planting

Planted on 1 June: in the first weeks water every 4 days.

Pests and diseases of zucchini to watch for:

Weather in Rennes during the zucchini season

About 404 mm of rain falls in the season; August is the driest month (48 mm) and October the wettest (87 mm).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
June	22.8	12.9	83	11	16:02
July	24.3	14.3	50	8	15:41
August	24.4	14.4	48	9	14:21
September	21.5	12.4	58	9	12:38
October	17.4	9.8	87	12	10:54
November	12.4	6.1	78	12	9:17

ERA5 2016–2025, Open-Meteo

Zucchini in nearby cities

Around Rennes, Nantes is 4 days earlier and Caen 14 days later.

City	Distance	Date	Difference
Nantes	99 km	28 May – 12 September	4 days earlier
Angers	110 km	28 May – 10 September	4 days earlier
Le Mans	140 km	31 May – 7 September	1 day earlier
Caen	154 km	15 June – 18 September	14 days later
Quimper	180 km	15 June – 22 September	14 days later
Tours	194 km	31 May – 10 September	1 day earlier

Where to buy zucchini plants and seeds near Rennes

Buy plants ready to set out from 1 June to 11 September (from 11 May to 11 September for an unheated greenhouse); seed for raising your own is sown from 20 April to 21 August. Within 15 km of Rennes OpenStreetMap lists 21 garden centres, 5 farm-supply shops, 3 plant nurseries, 41 markets and 19 farm shops (collected 20 October 2026).

Irvin — farm supply
Le Chemin Chaussé, 35250 Mouazé · 15 km · irvin.fr
Delourmel Agriculture — farm supply
Rue du Hil 11, 35230 Noyal-Châtillon-sur-Seiche · 4 km
La Criée, marché central — market
Mon–Thu 09:00–14:00, 15:30–19:00; Fri 09:00–19:30; Sat, Sun 09:00–19:00 · 0 km · lacriee-marchecentral.com
Marché de produits biologiques — market
Place de l'Église, 35510 Cesson-Sévigné · Wed 14:30–18:45 · 6 km · ville-cesson-sevigne.fr

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