Lobelias, also known as men's faithful, are known for their cushion-like growth and their large number of blue flowers. As winter approaches, is the end near or not?
Can lobelias stay outside in winter?
Are lobelias hardy? The annual Lobelia erinus is not hardy and must be replanted every year. Perennial herbaceous lobelias such as Lobelia cardinalis or Lobelia x speciosa can survive frosty temperatures if they are overwintered with winter protection or in a frost-free room.
Origin in Africa – not used to frost
Lobelias originally come from the southern parts of Africa. They are used to warmth there. They don't deal well with frost. Even a temperature of 0 °C can mean the difference between life and death. In short: Lobelias are not hardy in our latitudes.
Mostly annual in this country
The most common species commercially available in this country is Lobelia erinus. This specimen, of which there are many cultivars, is an annual. This means that when winter comes, this plant dies. You have to replant or sow them every year. But that's not a problem.
Sown, germinated, bloomed
Lobelias are fast-growing and bloom in summer, even if they were sown in spring. From January onwards, the seeds can be grown at home – ideally under glass. They are light germinators that prove to be extremely happy to germinate. The plants can go out from mid-May and they will be blooming at the end of May/beginning of June.
Perennial lobelias: They can be overwintered
So-called perennial lobelias are perennial. They become larger, have stronger growth and can tolerate some frost, but not for days. You shouldn't challenge them! It is better to provide these fellows with winter protection or to keep them indoors in a frost-free place.
How does wintering outside and in the bucket work?
Perennial lobelias that can survive the winter protected outside or in a cool room in this country include the following species:
- Lobelia cardinalis
- Lobelia sessilifolia
- Lobelia siphilitica
- Lobelia splendens
- Lobelia x gerardii (hybrid)
- Lobelia x speciosa (hybrid)
These lobelias should only be overwintered outside in warm regions such as wine-growing areas. They are cut down in autumn and covered with brushwood, leaves or pine branches in the root area. They can be overwintered in a bucket in a cool place of 5 to 10 °C.
Tip
If you try to overwinter lobelias, you shouldn't forget to care for them in the winter too. They must be supplied with water sparingly but regularly.