When to plant cucumbers in Sion: 28 June – 4 August

In Sion, cucumber: sow for seedlings from 10 May to 7 July; plant into a greenhouse from 7 June to 4 August; plant out into open ground from 28 June to 4 August. For plants and seeds, the places nearby include Ferme Vuissoz (farm shop, 2 km) and bioverger.ch (farm shop, 4 km); addresses and opening hours are below.

Cucumber in Sion: soil, season and weather

In Sion the soil, not frost, sets the date: the last frost is over around 8 May, but the top 7 cm of soil reaches 18 °C — the minimum on the cucumber card — only around 28 June, 51 days later.

Last spring frost	8 May
Top 7 cm of soil at 18 °C	28 June, 51 days after the last frost
Into an unheated greenhouse	7 June – 4 August; June outside: 9.5 °C at night, 20.2 °C by day; card 18–25 °C
First autumn frost	19 October, 113 days after the start
Days in the bed to the first harvest (card)	34
First harvest, if planted in this window	1 August – 7 September
Days left for picking	79
Daylight	15:30 on 31 May, 15:46 on 28 June
Watering outdoors when fruiting (card)	every 2 days; the driest month, September, has 12 rainy days

The same dates in Sion hold for Bell Pepper, Eggplant, Zucchini, Pumpkin and Watermelon.

Cucumber in Sion: care after planting

Planted on 28 June: in the first weeks water every 4 days.

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

5 July — feed: nitrogen

Pests and diseases of cucumber 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 Sion during the cucumber season

No month of the season averages above the cucumber card's 18–35 °C by day; the warmest, August, averages 22 °C. Months that stay below 18 °C even by day on average: September (17.7 °C) and October (13.7 °C). Nights average below 18 °C in every month of the season, from 2.9 °C to 11.1 °C.

Month	Day, °C	Night, °C	Rain, mm	Rainy days	Daylight on the 15th
June	20.2	9.5	125	18	15:46
July	21.8	11.1	115	16	15:27
August	22	10.8	103	14	14:12
September	17.7	7.1	91	12	12:36
October	13.7	2.9	105	12	10:59

ERA5 2016–2025, Open-Meteo

Cucumber in nearby cities

Around Sion, Neuchâtel is 22 days earlier and Aosta 3 days later.

City	Distance	Date	Difference
Aosta	55 km	1 July – 7 August	3 days later
Lausanne	65 km	19 June – 5 September	9 days earlier
Fribourg	65 km	21 June – 22 August	7 days earlier
Bern	80 km	21 June – 19 August	7 days earlier
Neuchâtel	91 km	6 June – 13 September	22 days earlier
Geneva	94 km	8 June – 2 September	20 days earlier

Where to buy cucumber plants and seeds near Sion

Buy plants ready to set out from 28 June to 4 August (from 7 June to 4 August for an unheated greenhouse); seed for raising your own is sown from 10 May to 7 July. Within 15 km of Sion OpenStreetMap lists 4 garden centres, 1 farm-supply shop, 1 plant nursery, 1 market and 4 farm shops (collected 27 October 2026).

Ferme Vuissoz — farm shop
Chemin de Maragnène 40, 1950 · 2 km · ferme-vuissoz.ch
Self-Service Bio — farm shop
Feb 15–Dec 31 Mon–Sat 10:00–19:00 · 14 km · reynard-biotop.ch
bioverger.ch — farm shop
24/7 · 4 km · bioverger.ch
Chez Cheseaux — farm shop
Mon–Sun 07:00–19:00 · 15 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