When to plant tomatoes in Karlsruhe: 10 May – 30 July

In Karlsruhe, tomato: sow for seedlings from 26 February to 8 June; plant into a greenhouse from 19 April to 30 July; plant out into open ground from 10 May to 30 July. For plants and seeds, the places nearby include Bambusgarten-Bulach (garden centre, 3 km) and Mauk Gartenwelt (garden centre, 7 km); addresses and opening hours are below.

Tomato in Karlsruhe: soil, season and weather

In Karlsruhe the soil, not frost, sets the date: the last frost is over around 5 April, but the top 7 cm of soil reaches 15 °C — the minimum on the tomato card — only around 10 May, 35 days later.

Last spring frost	5 April
Top 7 cm of soil at 15 °C	10 May, 35 days after the last frost
Into an unheated greenhouse	19 April – 30 July; April outside: 5.4 °C at night, 15.9 °C by day; card 16–27 °C
First autumn frost	19 November, 193 days after the start
Days in the bed to the first harvest (card)	70
First harvest, if planted in this window	19 July – 8 October
Days left for picking	123
Daylight	12:04 on 19 March, 15:02 on 10 May
Watering outdoors when fruiting (card)	every 3 days; the driest month, August, has 10 rainy days

Tomato in Karlsruhe: 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 Karlsruhe during the tomato season

No month of the season averages above the tomato card's 16–27 °C by day; the warmest, August, averages 26.4 °C. Months that stay below 16 °C even by day on average: November (9.6 °C). Nights average below 16 °C in May–July and September–November (3.4–15.8 °C).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
May	19.8	9.7	82	13	15:16
June	25.2	14.8	71	11	16:11
July	26.2	15.8	63	11	15:49
August	26.4	16.1	54	10	14:26
September	22	12.4	62	10	12:39
October	16.5	8.5	80	13	10:52
November	9.6	3.4	70	13	9:11

ERA5 2016–2025, Open-Meteo

Tomato in nearby cities

2 of the nearest cities share Karlsruhe's date.

City	Distance	Date	Difference
Mannheim	54 km	10 May – 31 July	same day
Stuttgart	62 km	18 May – 19 July	8 days later
Strasbourg	68 km	12 May – 31 July	2 days later
Saarbrücken	106 km	14 May – 29 July	4 days later
Wiesbaden	120 km	10 May – 3 August	same day
Freiburg im Breisgau	120 km	13 May – 27 July	3 days later

Where to buy tomato plants and seeds near Karlsruhe

Buy plants ready to set out from 10 May to 30 July (from 19 April to 30 July for an unheated greenhouse); seed for raising your own is sown from 26 February to 8 June. Within 15 km of Karlsruhe OpenStreetMap lists 25 garden centres, 3 farm-supply shops, 18 plant nurseries, 23 markets and 59 farm shops (collected 28 October 2026).

Bambusgarten-Bulach — garden centre
Landgrabenstraße 62a, 76135 Karlsruhe · Mar–Oct Sat 10:00–16:00 · 3 km · bambusgarten-bulach.de
Mauk Gartenwelt — garden centre
Bruchwaldstraße 63, 76229 · Mon–Fri 09:00–19:00; Sat 09:00–18:00; Sun 10:00–13:00; public holidays closed · 7 km · mauk-gartenwelt.de
Iben Gartencenter — garden centre
Hertzstraße 1, 76275 Ettlingen · Mon–Fri 08:00–18:00; Sat 08:00–13:00 · 7 km · garten-pflanzen.de
Ihr LandMarkt Faas — garden centre
Lorenzstraße 3a, 76297 Stutensee · Mon–Fri 08:30–18:00; Sat 09:00–13:00; Sun, public holidays closed · 8 km · faas-shop.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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