€0.00

Frost protection and the Ice Saints

"Before the Ice Saints there is no summer" – this old gardening rule has a true core. Late frosts in May can destroy warmth-loving young plants overnight, even if the days are already summery warm. Anyone who knows the Ice Saints and how to protect plants is on the safe side.

The rule of thumb: sensitive crops go outdoors only after 15 May – or are well protected when frost threatens.

Frost protection and the Ice Saints

In short

  • The Ice Saints fall around 11–15 May (up to "Cold Sophie").
  • Until then late frosts threaten, which can destroy warmth crops.
  • Protection: fleece, film, covers, bring pots inside, water in the evening.
  • Affected: tomatoes, peppers, cucumbers, beans, basil, courgette.

What are the Ice Saints?

The Ice Saints are a series of commemoration days in mid-May (Mamertus, Pancras, Servatius, Boniface and "Cold Sophie" on 15 May). Experience shows it can cool down significantly once more until then and freeze at night. Only afterwards is the risk of late frosts considered over in many regions.

Why frost is so dangerous

Warmth-loving plants do not tolerate frost: their cells burst below freezing, the leaves turn glassy and die off. A single frosty night can destroy tomatoes, peppers or basil – which is why protection is worthwhile.

How to protect your plants

  • Fleece & film: lay garden fleece or a film cover over the plants when frost is forecast.
  • Covers: upturned buckets, pots or cold-frame tops protect individual plants.
  • Bring pots inside: place container plants against a sheltered wall or indoors overnight.
  • Water in the evening: moist soil stores warmth and releases it at night.
  • Use the position: house walls and sheltered corners stay a little warmer at night.

Frequently asked questions

Does 15 May apply everywhere?
In mild regions you can plant a little earlier, in harsh and higher locations better wait a bit longer.

My plant had frost – is it done for?
Not always. Wait a few days; if it re-shoots from the healthy part, it can recover.

Tip

Keep an eye on the weather forecast and lay the fleece on in the evening – take it off again in the morning so it does not get too warm and damp during the day.

Caution

Take the frost risk seriously even in warm weather: clear, windless nights in May cool down especially strongly.

Anyone who starts with strong young plants after the Ice Saints saves time and is on the safe side. We raise our young plants to be robust.