When to plant tomatoes in Mannheim: 10 May – 31 July

In Mannheim, tomato: sow for seedlings from 26 February to 9 June; plant into a greenhouse from 19 April to 31 July; plant out into open ground from 10 May to 31 July. For plants and seeds, the places nearby include OBI Gartencenter (garden centre, 5 km) and Raiffeisen Mannheim eG (garden centre, 8 km); addresses and opening hours are below.

Tomato 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 15 °C — the minimum on the tomato card — only around 10 May, 26 days later.

Last spring frost	14 April
Top 7 cm of soil at 15 °C	10 May, 26 days after the last frost
Into an unheated greenhouse	19 April – 31 July; April outside: 5.3 °C at night, 15.7 °C by day; card 16–27 °C
First autumn frost	20 November, 194 days after the start
Days in the bed to the first harvest (card)	70
First harvest, if planted in this window	19 July – 9 October
Days left for picking	124
Daylight	12:04 on 19 March, 15:05 on 10 May
Watering outdoors when fruiting (card)	every 3 days; the driest month, August, has 11 rainy days

Tomato in Mannheim: care after planting

Planted on 10 May: in the first weeks water every 4 days.

Feeding, by the card’s schedule from that day:

10 May — feed: balanced (NPK)
7 June — feed: nitrogen

Pests and diseases of tomato to watch for:

Dates count from the first planting day of the window above; a later planting moves them by as many days.

Weather in Mannheim during the tomato season

No month of the season averages above the tomato card's 16–27 °C by day; the warmest, July, averages 26.2 °C. Months that stay below 16 °C even by day on average: November (9.3 °C). Nights average below 16 °C in May–July and September–November (3.6–15.8 °C).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
May	19.9	9.7	85	13	15:20
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

Tomato in nearby cities

2 of the nearest cities share Mannheim's date.

City	Distance	Date	Difference
Karlsruhe	54 km	10 May – 30 July	same day
Wiesbaden	68 km	10 May – 3 August	same day
Frankfurt	71 km	11 May – 28 July	1 day later
Stuttgart	94 km	18 May – 19 July	8 days later
Saarbrücken	111 km	14 May – 29 July	4 days later
Strasbourg	115 km	12 May – 31 July	2 days later

Where to buy tomato plants and seeds near Mannheim

Buy plants ready to set out from 10 May to 31 July (from 19 April to 31 July for an unheated greenhouse); seed for raising your own is sown from 26 February to 9 June. 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).

Raiffeisen Mannheim eG — garden centre
Kirschgartshäuser Straße 22-24, 68307 Mannheim · Mon–Fri 09:00–18:00; Sat 09:00–16:00 · 8 km · raiffeisen-mannheim.de
ZG Raiffeisen Markt — garden centre
Raiffeisenstraße 1, 68542 Heddesheim · Mon–Fri 08:30–18:30; Sat 08:30–14:00 · 11 km · zg-raiffeisen.de
OBI Gartencenter — garden centre
Industriestraße 45-49, 67063 Ludwigshafen am Rhein · Mon–Sat 08:00–20:00 · 5 km · obi.de
Bonsai Zentrum Heidelberg — garden centre
Mannheimer Straße 401, 69123 Heidelberg · Wed–Fri 14:00–18:00; Sat 10:00–16:00 · 13 km · bonsaizentrum-hd.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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