Like so many popular ornamental plants, geraniums (Pelargonium) are not native to us, but come from the hot and rather dry climate of southeast Africa. As a result, the popular balcony flowers cannot tolerate rainy or cold weather, so the question arises as to the optimal planting time.
When is the best time to plant geraniums?
The ideal planting time for geraniums is between mid and late May, after the so-called Ice Saints. This farmer's rule states that from mid-May the risk of night frosts decreases significantly. Geraniums tolerate temperatures below 10°C and frost poorly.
Geraniums do not tolerate frost
During the growing season, temperatures should not fall below 10 °C, otherwise the geraniums will stop growing - and thus also flowering. However, a short-term drop in temperature is not a problem as long as there is no frost. Night frost, especially late in spring, can quickly lead to the death of sensitive plants.
When to plant geraniums?
For this reason, geraniums should only be put outdoors after the Ice Saints, as from this point onwards the likelihood of night frosts decreases rapidly. The “Ice Saints” refer to a series of Christian saints who have their memorial days in mid-May and which conclude with “Cold Sophie” on May 15th. It is a centuries-old farming rule that is still used today. The best time to bring geraniums outside is probably between mid and late May - depending on the weather forecast for your area.
Harden off geraniums gradually?
However, you don't have to wait until the end of May to put your geraniums on the balcony. If the weather is right - temperatures above 10 °C and sunshine - this is possible as early as April, although the plants should then be brought into the house overnight. If you want to be on the safe side, don't hang up the balcony boxes with the geraniums right away, but first place them on a heat-emitting house wall directly in the sun.
Tip
However, don't wait too long to bring your geraniums out of hibernation - this should be done in March at the latest.