When to plant watermelons in Wiesbaden: 30 May – 14 August

In Wiesbaden, watermelon: sow for seedlings from 11 April to 17 July; plant into a greenhouse from 9 May to 14 August; plant out into open ground from 30 May to 14 August.

Watermelon in Wiesbaden: soil, season and weather

In Wiesbaden the soil, not frost, sets the date: the last frost is over around 5 April, but the top 7 cm of soil reaches 18 °C — the minimum on the watermelon card — only around 30 May, 55 days later.

Last spring frost	5 April
Top 7 cm of soil at 18 °C	30 May, 55 days after the last frost
Into an unheated greenhouse	9 May – 14 August; May outside: 9.9 °C at night, 19.9 °C by day; card 18–35 °C
First autumn frost	23 November, 177 days after the start
Days in the bed to the first harvest (card)	59
First harvest, if planted in this window	28 July – 12 October
Days left for picking	118
Daylight	14:44 on 2 May, 16:00 on 30 May
Watering outdoors when fruiting (card)	every 5 days; the driest month, August, has 9 rainy days

The same dates in Wiesbaden hold for Cucumber, Bell Pepper, Eggplant, Zucchini and Pumpkin.

Watermelon in Wiesbaden: care after planting

Planted on 30 May: in the first weeks water every 5 days.

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

30 May — feed: balanced (NPK)

Pests and diseases of watermelon 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 Wiesbaden during the watermelon season

No month of the season averages above the watermelon card's 18–35 °C by day; the warmest, August, averages 26.1 °C. Months that stay below 18 °C even by day on average: October (15.7 °C) and November (9 °C). Nights average below 18 °C in every month of the season, from 3.4 °C to 15.8 °C.

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
May	19.9	9.9	66	12	15:24
June	25.1	14.7	59	11	16:21
July	25.9	15.7	64	10	15:59
August	26.1	15.8	56	9	14:32
September	21.6	12.1	56	9	12:41
October	15.7	8	63	13	10:49
November	9	3.4	57	13	9:04

ERA5 2016–2025, Open-Meteo

Watermelon in nearby cities

1 of the nearest cities share Wiesbaden's date.

City	Distance	Date	Difference
Frankfurt	32 km	4 June – 8 August	5 days later
Mannheim	68 km	1 June – 11 August	2 days later
Bonn	108 km	4 June – 10 August	5 days later
Karlsruhe	120 km	30 May – 10 August	same day
Saarbrücken	130 km	3 June – 9 August	4 days later
Cologne	132 km	3 June – 11 August	4 days later

Where to buy watermelon plants and seeds near Wiesbaden

Buy plants ready to set out from 30 May to 14 August (from 9 May to 14 August for an unheated greenhouse); seed for raising your own is sown from 11 April to 17 July. Within 15 km of Wiesbaden OpenStreetMap lists 18 garden centres, 1 farm-supply shop, 6 plant nurseries, 17 markets and 28 farm shops (collected 28 October 2026).

Flörsheimer Wochenmarkt - Gallusplatz — market
Gallusplatz, 65439 Flörsheim am Main · Fri 08:00–14:00 · 15 km
Mainzer Wochenmarkt — market
Tue 07:00–14:00; Fri–Sat 07:00–14:00 · 9 km
Wochenmarkt — market
Fri 09:00–12:00 · 11 km
Wochenmarkt Hochheim — market
Sat 07:00–13:00 · 11 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.

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