Thanks to the lush flowers, clematis are so popular that they are allowed to inhabit the whole planet. Nature has produced a great variety of varieties, as have the breeders. They are all perennials, but not all clematis are hardy. In this country, you can savor the autumnal rays of sunshine and drive the last blossoms outdoors. But then their owner must initiate the appropriate hibernation for each climbing specimen.
Table of Contents
hardiness
The colorful clematis family, as the clematis is also called, includes more than 300 varieties. Eager breeders regularly provide offspring to complement their colorful buds with ever more impressive variants.
The hardiness of a variety depends on the climate of its region of origin, with hybrids usually inheriting the characteristics of their parents. Roughly speaking, the following guidelines can be given:
- Australian clematis are not hardy
- Japanese and Chinese clematis tolerate up to -12 degrees
- Clematis varieties of European origin are considered hardy
- depending on the variety, these tolerate -20 to -37 degrees Celsius
Evergreen clematis usually do not tolerate frost, while perennial specimens survive -25 degrees Celsius unscathed.
What variety is my clematis?
Are you one of those plant lovers who know all their plants by variety name? If so, then that’s wonderful. If necessary, supplement this knowledge with data on winter hardiness by late summer at the latest.
Anyone who owns a beautiful but unknown clematis faces the question of how to overwinter it with the approaching frost. If it is not answered correctly, the clematis can freeze to death. Here are a few suggestions that may help you:
- Find variety names based on the flowers
- Ask previous owners, donors, acquaintances
- Research garden literature or the Internet
- ask at a nursery
If your detective work was unsuccessful, you can overwinter the climbing plant like a non-hardy variety to be on the safe side. This may require some effort, but it will certainly save the life of the clematis into the next year.
wintering factors
Two factors play important roles in hibernation:
- the hardiness of the variety
- the type of cultivation (open field or tub)
Clematis that are hardy are usually planted outside, where they get plenty of room to climb. Clematis that are not hardy, on the other hand, almost always root in a pot. But it is quite possible to handle it differently. But then overwintering has to be done differently.
Instructions for hardy varieties
When winter is announced, the clematis says goodbye to its industriousness, loses leaves and flowers. Not much can be seen of the once magnificent climbing plant. Hardy varieties usually do not need any protection to survive the frost unscathed. But there are exceptions, because not everyone tolerates the same amount of cold.
pruning
Before overwintering, all perennial clematis should first be cut back to around 20 to 40 cm. For other clematis you can follow the instructions for the respective pruning group. However, experts now recommend an autumn pruning for all varieties. The increasingly mild winters lead to early budding, which can easily be damaged by pruning measures in spring.
Planted clematis
All planted specimens that are hardy tolerate sub-zero temperatures. However, the tolerance limit depends on the variety. It doesn’t hurt if none of the vines have to freeze too much. Caring owners can e.g. Protect B as follows:
- spread a thick layer of foliage
- put fir fronds in the ground all around
Clematis in the bucket
A climber planted in a bucket feels the cold from all sides. Most of the bucket is surrounded by frigid air, quickly freezing the soil inside. Although the hardy clematis can stay outside all year round, there is still a need to protect them from the cold.
- take protective measures in the fall
- before the first frost
- Wrap the pot several times with fleece, foil or jute
- Cover the substrate with leaves, brushwood or wood shavings
- Bark mulch, on the other hand, is unsuitable
- Place the vine in a sheltered spot
- preferably on a wall under the eaves
- Place the pot on an insulating wooden board
young plants
These climbing plants only develop their full winter hardiness over the years. Young plants are therefore more sensitive to cold than adult specimens. In the case of hardy clematis that have just been planted out, there is therefore no choice, but rather an obligation to keep their root area warmer with suitable cover.
Basically, you should have planted out a young plant by September at the latest, so that it has enough time to conquer the new soil with its roots.
care in winter
The maintenance instructions are brief. It only includes the points fertilizing and watering. Hardy varieties receive the last fertilizer in September, after which the nutrient supply is completely suspended. Only in March may be fertilized again for the first time.
When wintering outdoors, clematis usually do not need additional water, since the soil is usually moist enough. Potted plants that are outside under an eaves and don’t get any rain should get a little watering every now and then.
Instructions for non-hardy varieties
Varieties that are not hardy usually thrive in large pots that are placed outside for the warm season. Occasionally, a non-hardy clematis is planted in the garden. In both cases, frost spells their downfall. A variety that is not hardy must necessarily move to a frost-free quarter. If she also needs a larger pot at the same time, she should get it by September at the latest. Otherwise, repotting will have to wait until spring.
Not hardy climber in the bucket
When the nights get colder, non-hardy plants need to be protected from frost. This is usually the case in October. A sheltered place outdoors and covers are not enough, a suitable winter quarters must be found. The new location should meet the following conditions:
- Room temperature from 5 to 10 degrees Celsius
- bright daylight for evergreen clematis
- but no direct sunlight
- Deciduous clematis can also be darker
- Ambient air should be dry
- Garage, garden shed or basement with window are ideal
Planted specimens
Non-hardy clematis that are planted out cannot survive a sub-zero winter outdoors. That’s why they have to be dug up by September at the latest.
- Plant a climbing plant in a pot
- bring to winter quarters early
To cut
If a clematis variety is not hardy, it should be cut back after the flowering season, but no later than early autumn. It should not be waited until wintering begins. An exception is the evergreen variant, for which spring is better suited for a cut.
Care in winter quarters
The fertilization of frost-sensitive clematis is already stopped in September, only the evergreen clematis is supplied with fertilizer until the end of October. In the winter quarters, fertilization is only applied cautiously from April.
Clematis in winter quarters must be watered so that the soil does not dry out completely. The evergreen vine requires more water than its leafless relatives. But be careful, too much moisture can lead to mold growth. Pour modestly, having previously done the finger test.
Take a regular look at your plant, as pests are more likely to spread in the winter quarters. If you discover them in time, you can save your climbing plant in the spring with suitable measures.
end of hibernation
The end of the winter period does not depend on the calendar, but on the current weather. The purpose of hibernation is protection against frost, and this can even be seen in this country until mid-May.
- Outdoors, budding begins around April
- then remove all protective covers
- Pots under the eaves can change their location
- Only put out non-hardy varieties when the danger of frost has passed
- outside it should be at least 5 degrees Celsius
