When to plant tomatoes in Hasselt: 10 May – 29 July

In Hasselt, tomato: sow for seedlings from 26 February to 7 June; plant into a greenhouse from 19 April to 29 July; plant out into open ground from 10 May to 29 July. For plants and seeds, the places nearby include Plantencentrum Vanstraelen - Priori (garden centre, 2 km) and Aveve (garden centre, 3 km); addresses and opening hours are below.

Tomato in Hasselt: soil, season and weather

In Hasselt the soil, not frost, sets the date: the last frost is over around 19 April, but the top 7 cm of soil reaches 15 °C — the minimum on the tomato card — only around 10 May, 21 days later.

Last spring frost	19 April
Top 7 cm of soil at 15 °C	10 May, 21 days after the last frost
Into an unheated greenhouse	19 April – 29 July; April outside: 4.9 °C at night, 14.8 °C by day; card 16–27 °C
First autumn frost	18 November, 192 days after the start
Days in the bed to the first harvest (card)	70
First harvest, if planted in this window	19 July – 7 October
Days left for picking	122
Daylight	12:04 on 19 March, 15:15 on 10 May
Watering outdoors when fruiting (card)	every 3 days; the driest month, September, has 11 rainy days

Tomato in Hasselt: 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 Hasselt during the tomato season

No month of the season averages above the tomato card's 16–27 °C by day; the warmest, August, averages 23.9 °C. Months that stay below 16 °C even by day on average: October (15.8 °C) and November (10.1 °C). Nights average below 16 °C in every month of the season, from 4.4 °C to 14.3 °C.

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
May	19.2	8.8	68	11	15:31
June	23	13.2	79	13	16:30
July	23.8	14	77	12	16:06
August	23.9	14.3	70	12	14:36
September	20.6	11.5	65	11	12:42
October	15.8	9.1	78	14	10:47
November	10.1	4.4	74	14	8:58

ERA5 2016–2025, Open-Meteo

Tomato in nearby cities

2 of the nearest cities share Hasselt's date.

City	Distance	Date	Difference
Liège	37 km	16 May – 30 July	6 days later
Leuven	45 km	10 May – 2 August	same day
Namur	61 km	16 May – 26 July	6 days later
Brussels	70 km	16 May – 2 August	6 days later
Antwerp	73 km	10 May – 2 August	same day
Charleroi	86 km	16 May – 26 July	6 days later

Where to buy tomato plants and seeds near Hasselt

Buy plants ready to set out from 10 May to 29 July (from 19 April to 29 July for an unheated greenhouse); seed for raising your own is sown from 26 February to 7 June. Within 15 km of Hasselt OpenStreetMap lists 21 garden centres, 1 farm-supply shop, 1 plant nursery, 2 markets and 14 farm shops (collected 27 October 2026).

Plantencentrum Vanstraelen - Priori — garden centre
Diepenbekerweg 51, Hasselt · Mon–Sat 09:00–18:00; Sun, public holidays 10:00–17:00 · 2 km · vanstraelen-priori.be
Aveve — garden centre
Evence Coppéelaan 42;54, 3600 Genk · Mon–Sat 09:00–18:00 · 12 km · aveve.be
Aveve — garden centre
Eikaart 15, 3740 Bilzen · Mon 13:00–18:00; Tue–Fri 09:00–18:00; Sat 09:00–17:00 · 14 km · aveve.be
Aveve — garden centre
Genkersteenweg 301, 3500 Hasselt · Mon–Fri 09:00–18:30; Sat 09:00–18:00 · 3 km · aveve.be

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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