When to plant watermelons in Liège: 4 June – 10 August

In Liège, watermelon: sow for seedlings from 16 April to 13 July; plant into a greenhouse from 14 May to 10 August; plant out into open ground from 4 June to 10 August.

Watermelon in Liège: soil, season and weather

In Liège the soil, not frost, sets the date: the last frost is over around 16 April, but the top 7 cm of soil reaches 18 °C — the minimum on the watermelon card — only around 4 June, 49 days later.

Last spring frost	16 April
Top 7 cm of soil at 18 °C	4 June, 49 days after the last frost
Into an unheated greenhouse	14 May – 10 August; May outside: 8.7 °C at night, 18.6 °C by day; card 18–35 °C
First autumn frost	19 November, 168 days after the start
Days in the bed to the first harvest (card)	59
First harvest, if planted in this window	2 August – 8 October
Days left for picking	109
Daylight	15:04 on 7 May, 16:15 on 4 June
Watering outdoors when fruiting (card)	every 5 days; the driest month, August, has 12 rainy days

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

Watermelon in Liège: care after planting

Planted on 4 June: in the first weeks water every 5 days.

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

4 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 Liège during the watermelon season

No month of the season averages above the watermelon card's 18–35 °C by day; the warmest, August, averages 23.5 °C. Months that stay below 18 °C even by day on average: October (15.6 °C) and November (10 °C). Nights average below 18 °C in every month of the season, from 4.5 °C to 14.4 °C.

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
June	22.5	13.1	84	12	16:27
July	23.3	14	72	13	16:04
August	23.5	14.4	66	12	14:35
September	20.3	11.7	74	12	12:41
October	15.6	9.2	74	13	10:48
November	10	4.5	68	14	9:00

ERA5 2016–2025, Open-Meteo

Watermelon in nearby cities

Around Liège, Hasselt is 5 days earlier and Namur 7 days later.

City	Distance	Date	Difference
Hasselt	37 km	30 May – 9 August	5 days earlier
Namur	53 km	11 June – 6 August	7 days later
Leuven	67 km	31 May – 13 August	4 days earlier
Charleroi	84 km	10 June – 6 August	6 days later
Brussels	89 km	8 June – 13 August	4 days later
Ettelbruck	95 km	6 June – 6 August	2 days later

Where to buy watermelon plants and seeds near Liège

Buy plants ready to set out from 4 June to 10 August (from 14 May to 10 August for an unheated greenhouse); seed for raising your own is sown from 16 April to 13 July. Within 15 km of Liège OpenStreetMap lists 11 garden centres, 3 plant nurseries, 7 markets and 12 farm shops (collected 27 October 2026).

Marché mardi matin — market
7 km
Marché du mercredi PM — market
11 km
Wallifungi — farm shop
3 km · wallifungi.be
Ferme Lejeune — farm shop
10 km · ferme-lejeune-hognoul.business.site

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.

Questions