When to plant zucchini in Leuven: 31 May – 5 September

In Leuven, zucchini: sow for seedlings from 19 April to 15 August; plant into a greenhouse from 10 May to 5 September; plant out into open ground from 31 May to 5 September.

Zucchini in Leuven: soil, season and weather

In Leuven the soil, not frost, sets the date: the last frost is over around 19 April, but the top 7 cm of soil reaches 18 °C — the minimum on the zucchini card — only around 31 May, 42 days later.

Last spring frost	19 April
Top 7 cm of soil at 18 °C	31 May, 42 days after the last frost
First autumn frost	22 November, 175 days after the start
Days in the bed to the first harvest (card)	36
First harvest, if planted in this window	6 July – 11 October
Days left for picking	139
Daylight	15:15 on 10 May, 16:10 on 31 May
Watering outdoors when fruiting (card)	every 3 days; the driest month, September, has 11 rainy days

The same dates in Leuven hold for Cucumber, Bell Pepper, Eggplant, Pumpkin and Watermelon.

Zucchini in Leuven: care after planting

Planted on 31 May: in the first weeks water every 4 days.

Pests and diseases of zucchini to watch for:

Weather in Leuven during the zucchini season

About 511 mm of rain falls in the season; September is the driest month (62 mm) and June the wettest (81 mm).

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
May	19.1	8.8	69	11	15:30
June	22.7	13.1	81	12	16:30
July	23.5	14	79	12	16:06
August	23.7	14.3	69	13	14:36
September	20.6	11.8	62	11	12:42
October	15.9	9.3	81	13	10:47
November	10.2	4.7	70	14	8:59

ERA5 2016–2025, Open-Meteo

Zucchini in nearby cities

Around Leuven, Hasselt is 1 day earlier and Namur 11 days later.

City	Distance	Date	Difference
Brussels	25 km	8 June – 5 September	8 days later
Antwerp	43 km	31 May – 5 September	same day
Hasselt	45 km	30 May – 1 September	1 day earlier
Namur	47 km	11 June – 29 August	11 days later
Charleroi	55 km	10 June – 29 August	10 days later
Liège	67 km	4 June – 2 September	4 days later

Where to buy zucchini plants and seeds near Leuven

Buy plants ready to set out from 31 May to 5 September (from 10 May to 5 September for an unheated greenhouse); seed for raising your own is sown from 19 April to 15 August. Within 15 km of Leuven OpenStreetMap lists 31 garden centres, 1 plant nursery, 7 markets and 21 farm shops (collected 27 October 2026).

Markt in Heverlee — market
Lodewijk Engelbertus Van Arenbergplein, 3001 Leuven · Sun 08:00–13:00 · 2 km
Markt in Wijgmaal — market
Mon 15:00–19:00 · 5 km · visitleuven.be
Markt — market
Tue 14:00–18:00 · 13 km
Bloemenmarkt — market
Thu 13:00–18:00 · 0 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.

Questions