When to plant zucchini in Mannheim: 1 June – 3 September

In Mannheim, zucchini: sow for seedlings from 20 April to 13 August; plant into a greenhouse from 11 May to 3 September; plant out into open ground from 1 June to 3 September. For plants and seeds, the places nearby include Agrartechnik Zentrum Mutterstadt (farm supply, 10 km) and Apfelhof Schulz (farm supply, 15 km); addresses and opening hours are below.

Zucchini in Mannheim: soil, season and weather

In Mannheim the soil, not frost, sets the date: the last frost is over around 14 April, but the top 7 cm of soil reaches 18 °C — the minimum on the zucchini card — only around 1 June, 48 days later.

Last spring frost	14 April
Top 7 cm of soil at 18 °C	1 June, 48 days after the last frost
First autumn frost	20 November, 172 days after the start
Days in the bed to the first harvest (card)	36
First harvest, if planted in this window	7 July – 9 October
Days left for picking	136
Daylight	15:08 on 11 May, 15:59 on 1 June
Watering outdoors when fruiting (card)	every 3 days; the driest month, August, has 11 rainy days

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

Zucchini in Mannheim: 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 Mannheim during the zucchini season

About 425 mm of rain falls in the season; August is the driest month (63 mm) and October the wettest (84 mm).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
June	25.3	14.7	69	11	16:15
July	26.2	15.8	67	10	15:53
August	26.2	16	63	11	14:28
September	21.8	12.2	69	10	12:40
October	16.1	8.4	84	13	10:51
November	9.3	3.6	73	14	9:08

ERA5 2016–2025, Open-Meteo

Zucchini in nearby cities

Around Mannheim, Karlsruhe is 2 days earlier and Stuttgart 4 days later.

City	Distance	Date	Difference
Karlsruhe	54 km	30 May – 2 September	2 days earlier
Wiesbaden	68 km	30 May – 6 September	2 days earlier
Frankfurt	71 km	4 June – 31 August	3 days later
Stuttgart	94 km	5 June – 22 August	4 days later
Saarbrücken	111 km	3 June – 1 September	2 days later
Strasbourg	115 km	1 June – 3 September	same day

Where to buy zucchini plants and seeds near Mannheim

Buy plants ready to set out from 1 June to 3 September (from 11 May to 3 September for an unheated greenhouse); seed for raising your own is sown from 20 April to 13 August. Within 15 km of Mannheim OpenStreetMap lists 30 garden centres, 3 farm-supply shops, 17 plant nurseries, 24 markets and 50 farm shops (collected 28 October 2026).

Apfelhof Schulz — farm supply
Brunnweg 7, 69469 Weinheim · 24/7 · 15 km · apfelhof-schulz.de
Agrartechnik Zentrum Mutterstadt — farm supply
Mühlweg 1, 67112 Mutterstadt · Mar–Oct Mon–Fri 07:30–18:00; Mar–Oct Sat 08:00–12:00; Nov–Feb Mon–Fri 07:30–17:00 · 10 km
Stadtteilmarkt Schwetzingerstadt — market
Otto-Beck-Straße, 68165 Mannheim · Fri 07:00–13:30 · 2 km · ep-ma.de
Marktplatz — market
G1 · 24/7 · 0 km · ep-ma.de

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.

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