Greenly

Zurich: frost dates

Switzerland

In Zurich the last spring frost usually comes around 14 April and the first autumn frost around 16 November, which leaves about 216 frost-free days (median of 2016–2025). Tomato seedlings can go into open ground around 29 May.

Last spring frostaround 14 April
First autumn frostaround 16 November
Frost-free days216 days

Median of 2016–2025 for the 25 km grid cell of the city: the last day at or below 0 °C in spring and the first in autumn (ERA5 reanalysis via Open-Meteo). In a cold year a frost can come a week or two later — Greenly warns 48 hours ahead.

When to sow and plant

CropSow for seedlingsPlant out in a greenhouseOpen ground
Bell Pepper8 March21 May11 June
Chili Pepper15 March28 May18 June
Corn—14 Aprilsow 5 May
Cucumber9 April21 May11 June
Eggplant12 March21 May11 June
Green Beans8 March14 April5 May
Melon30 March21 May11 June
Peas—3 Marchsow 24 March
Physalis24 March8 May29 May
Pumpkin1 April8 May29 May
Sweet Corn—14 Aprilsow 5 May
Tomato12 March8 May29 May
Watermelon19 April21 May11 June
Zucchini6 April8 May29 May

Planting out: a week after the last frost once the soil is warm enough for the crop; frost-hardy crops three weeks before it; an unheated greenhouse three weeks earlier. Seedlings are sown so they are ready on that day.

Planted in autumn

CropPlant around
Crocus17 October
Daffodil17 October
Garlic17 October
Hyacinth17 October
Lily17 October
Tulip17 October

A month before the first autumn frost, so the roots grow before winter.