Cold Sophie on May 15, 2025: What are the Ice Saints?

Whether it's "Frosty Sophie," "Sheep's Cold," or the Ice Saints: according to farmers' proverbs, there are numerous frosty weather phenomena in spring. Even today, many people still heed these wisdoms. What the May days are all about and what hobby gardeners should pay particular attention to – we've compiled the most important facts about the Ice Saints.

The Ice Saints, feared by gardeners, occur on the same days every year:

• Ice Saints in Northern Germany: May 11 to 15
• Ice Saints in Southern Germany: May 12 to 14

The fact that the Ice Saints begin a day later in southern Germany than in the north is explained by the gradual advance of cold air from the north. May 15th – the name day of Saint Sophia – is often included in this celebration. Therefore, a cold phenomenon felt on this day is often called "cold Sophie" by many.

“The cold currents do not necessarily have to hit us at this exact time – early or late Ice Saints are also possible,” says expert Jung.

The five days of the Ice Saints are named after the name days of real saints:

• Mamertus (May 11): Mamertus, the first Ice Saint, was Bishop of Vienne near Lyon in the fifth century and is said to have performed several miracles, including stopping a fire. Mamertus was sought for assistance in cases of fever, severe drought, or chest diseases.
• Pancras (May 12): His name means "the one who conquers all." The second Ice Saint is one of the first martyrs and was executed in Rome at the beginning of the fourth century.
• Servatius (May 13): The then bishop of Belgium is said to have predicted the Hun invasion of Europe, which actually occurred around 450 AD. The third Ice Saint was invoked for help in cases of frost damage, foot diseases, and rat plagues.
• Boniface of Tarsus (May 14): His name means "the one who promises good fortune." He converted to Christianity late in life but died a martyr shortly thereafter.
• Sophia of Rome (May 15): Also known as "Cold Sophia," she was often prayed for assistance during late frosts and for a good harvest. Sophia is often depicted with a trough and sword, but also with a palm frond and a book.

Knowing and heeding a few farmer's rules doesn't hurt. This way, you'll internalize rough periods when the weather often changes dramatically—as is the case in early to mid-May. Those who wait until after this time to start designing their summer garden and balcony should be on the safe side when it comes to the risk of frost.

• No summer before Boniface, no frost after Sophie.
• Cold Sophie does everything here.
• If it freezes on St. Pancras, a lot of things in the garden will be ruined.
• Pankraz, Servaz, Bonifaz only make way for the summer.
• Never plant before cold weather.
• Pankraz and Servaz are two evil brothers who destroy what spring has brought.
• You are never safe from night frost until Sophie has passed.
• Servaz must be over if you want to be safe from night frost.

However, if you sow or plant your vegetables too early, or plant your garden with cold-sensitive flowers, you can expect your plants to die. Even cold-sensitive potted plants are best left outdoors only when temperatures consistently exceed ten degrees Celsius.

If you dare to do it beforehand, you should keep an eye on the weather forecast and bring the potted plants back into the house if there is frost or wrap them up warmly in fleece overnight.

Fleece and brushwood provide temporary protection. Special film can also protect plants from night frost. This is a temporary solution, as plants need plenty of light, especially during the growth phase. Furthermore, moisture can quickly collect under the tarpaulin, causing air to build up.

The Ice Saints go back to centuries-old reports from farmers: They observed the weather and atmospheric conditions and learned that on the saints' name days there was often a final cold air front and thus corresponding night frosts.

The farmers' rules for the Ice Saints refer to late frosts in spring, which are regularly recorded in Germany until around mid-May. According to the German Weather Service, this is due to weather conditions caused by arctic polar air, which frequently occur at this time of year.

But "often" doesn't mean "always." And depending on the weather during the year, the frost period can end much earlier. For example, the German Weather Service sometimes renames the Ice Saints the "Sweat Saints," with daily highs exceeding 25 degrees Celsius in some years. In other years, depending on the weather, they can become "Snow Saints."

Therefore, the farmers' sayings about the Ice Saints are only considered a rough guide and not hard and fast rules. Furthermore, there are now scientifically sophisticated weather forecasts that gardeners can rely on more easily.

From a meteorological perspective, this phenomenon is related to the fact that the European mainland warms rapidly in May, while the ocean often remains cold. Low-pressure areas form. The air masses shift, and the warm air currents from the mainland move northward. This, in turn, pushes icy cold currents onto the mainland. "The cold front comes from Scandinavia and often originates in the polar air," explains meteorologist Dominik Jung.

As esteemed as they are here, the Ice Saints are not just a phenomenon in German-speaking countries. These days are also known in other European countries and even on the US East Coast. In France, for example, they are called "Saints de glace," in Poland "Zimni ogrodnicy," and in England "Ice Saints."