When to plant watermelons in Hradec Králové: 7 June – 2 August

In Hradec Králové, watermelon: sow for seedlings from 19 April to 5 July; plant into a greenhouse from 17 May to 2 August; plant out into open ground from 7 June to 2 August. For plants and seeds, the places nearby include John zahradnictví s.r.o. (garden centre, 3 km); addresses and opening hours are below.

Watermelon in Hradec Králové: soil, season and weather

In Hradec Králové the soil, not frost, sets the date: the last frost is over around 18 April, but the top 7 cm of soil reaches 18 °C — the minimum on the watermelon card — only around 7 June, 50 days later.

Last spring frost	18 April
Top 7 cm of soil at 18 °C	7 June, 50 days after the last frost
Into an unheated greenhouse	17 May – 2 August; May outside: 8.3 °C at night, 18.4 °C by day; card 18–35 °C
First autumn frost	11 November, 157 days after the start
Days in the bed to the first harvest (card)	59
First harvest, if planted in this window	5 August – 30 September
Days left for picking	98
Daylight	15:10 on 10 May, 16:15 on 7 June
Watering outdoors when fruiting (card)	every 5 days; the driest month, November, has 10 rainy days

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

Watermelon in Hradec Králové: care after planting

Planted on 7 June: in the first weeks water every 5 days.

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

7 June — 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 Hradec Králové during the watermelon season

No month of the season averages above the watermelon card's 18–35 °C by day; the warmest, August, averages 24.8 °C. Months that stay below 18 °C even by day on average: October (14.4 °C) and November (7.5 °C). Nights average below 18 °C in every month of the season, from 1.7 °C to 14.6 °C.

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
June	23.7	13.2	78	12	16:23
July	24.6	14.4	76	12	16:00
August	24.8	14.6	91	11	14:32
September	20.4	11	79	9	12:41
October	14.4	6.6	59	12	10:49
November	7.5	1.7	45	10	9:03

ERA5 2016–2025, Open-Meteo

Watermelon in nearby cities

Around Hradec Králové, Prague is 4 days earlier and Liberec 15 days later.

City	Distance	Date	Difference
Pardubice	19 km	5 June – 1 August	2 days earlier
Liberec	83 km	22 June – 23 July	15 days later
Prague	100 km	3 June – 30 July	4 days earlier
Olomouc	123 km	3 June – 28 July	4 days earlier
Brno	126 km	6 June – 28 July	1 day earlier
Wrocław	131 km	5 June – 2 August	2 days earlier

Where to buy watermelon plants and seeds near Hradec Králové

Buy plants ready to set out from 7 June to 2 August (from 17 May to 2 August for an unheated greenhouse); seed for raising your own is sown from 19 April to 5 July. Within 15 km of Hradec Králové OpenStreetMap lists 4 garden centres, 1 farm-supply shop and 4 farm shops (collected 28 October 2026).

Okrasné zahradnictví Havlíček — garden centre
15 km
Ovocné sady Vyčítal — farm shop · sells: apple, cherry
9 km
Ivo Košťál — farm shop · sells: apple
9 km
John zahradnictví s.r.o. — garden centre
Pražská třída 16/106, 50004 · Mon–Fri 08:00–18:00; Sat 08:00–16:00; Sun 09:00–16:00 · 3 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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