- origin
- growth
- leaves
- blossoms
- fruit
- Which location is suitable?
- What soil does the plant need?
- The right planting distance
- How do I plant correctly?
- Pour corkscrew hazel
- Fertilize corkscrew hazel properly
- Cut corkscrew hazel correctly
- Propagating corkscrew hazel
- pests
- tip
- sorts
With its bizarrely twisted branches, the corkscrew hazel is a real curiosity among ornamental trees. It is not entirely clear where the peculiar branch deformation comes from. What is certain, however, is that with its structurally rich shrubbery it makes a whimsical and romantic image in the garden.
The corkscrew hazel is a beautiful addition to the garden
Table of Contents
Show all- origin
- growth
- leaves
- blossoms
- fruit
- Which location is suitable?
- What soil does the plant need?
- The right planting distance
- How do I plant correctly?
- Pour corkscrew hazel
- Fertilize corkscrew hazel properly
- Cut corkscrew hazel correctly
- Propagating corkscrew hazel
- pests
- tip
- sorts
- Bizarrely winding branches either spontaneous mutation or harmless disease
- First discovered and described in England around 1900
- Today targeted "manufacture" of the corkscrew hazel through refinement
- Very popular again at the moment
- Like common hazel, upright, multi-stemmed shrub growth
- Fast growing, up to 6 m tall and around 4 m wide
- Branches twisted like a corkscrew
- Age up to 100 years
- Are also marked by the mutation or disease and show a curly structure
- Size and shape as with common hazel: rounded, pointed at the front, double-serrated edge
- Light green color, slightly hairy
- Yellow autumn colour, leaves are completely shed in winter
- Corkscrew hazel is monoecious with male and female flowers on one specimen
- Male flowers in catkin shape, female flowers budded with reddish tip
- Flowering time in February to March
- Pollen is allergenic, but an important food source for bees in the early part of the year
- Less productive than common hazel
- Nuts also less tasty
- Better plant common hazel for a good nut yield
- Soil for corkscrew hazel as nutritious and humic as possible
- Well drained and moist
- As warm as possible
- pH rather high
- In itself, corkscrew hazel does not need pruning care
- 1. Exception: After any transplanting
- 2. Exception: Formation of wild shoots that disturb the characteristic twig appearance and overgrow - cut off close to the ground
- Radical pruning possible in old individuals
origin
The corkscrew hazel is a modified variant of the common hazel, Corylus avellana. Its botanical variety name is Corylus avellana 'Contorta'. Unlike the corkscrew willow, which shows a similarly twisted branch system but otherwise has a different habit, the corkscrew hazel is not a deliberate breed. Rather, it is a whim of nature. Experts don't quite agree on whether a spontaneous mutation, i.e. a genetic error, or a disease that does not further affect the shrub is responsible.
This wondrous form of hazel was first discovered and described around 1900 in England. Impressed by the eye-catching branch structure, people have long since started to deliberately use the shape through refinement. The common hazel usually serves as a base for this.
Just like the corkscrew willow, which is sometimes confused with the corkscrew hazel due to the relationship in branch structure and naming, the corkscrew hazel is currently experiencing a real boom in gardens. Above all, one not only enjoys the original branch structure directly on the bush, but also likes to use individual twigs as a puristic decoration in the vase.
Origin at a glance:
growth
In terms of its basic habit, Corylus avellana 'Contorta' does not differ significantly from the common hazel. Like them, it also grows as a multi-stemmed, upright shrub with quite profuse sympodial branching. With rapid growth, the corkscrew hazel can reach 4 to 6 meters in height and around 2 to 4 meters in width. Their crown can become quite expansive and slightly overhanging with age.
Their most characteristic and most striking feature are of course their corkscrew-like twisted branches, which not only look very decorative on the bush, but also as a cutting. Especially when there are no leaves over the winter, the twisted branches can set a striking structural accent in the garden.
The corkscrew hazel can live up to 100 years.
Growth characteristics in keywords:
leaves
The leaves are also marked by the mutation or the disease that gives the corkscrew hazel its name and its special status: Because they are not as smooth and straight as those of the common hazel. They show a slightly ruffled, wrinkled structure and thus take up the motto of the branch factory.
In terms of size, color and edge structure, however, they do not differ from the leaves of the common hazel: They also have a typically rounded, pointed shape with a double-serrated edge and are light green in color. Their texture is finely veined, but appears coarser due to the curling. The surface is slightly hairy. They attach alternately to the branches. In autumn, like the common hazel, the foliage turns yellow and is completely shed by winter.
Sheet properties in brief:
blossoms
Like its original form, the corkscrew hazel is monoecious - both male and female flowers are formed on one specimen. The male flowers are already formed in autumn and then form the greenish-yellowish catkins so typical of hazel at the end of winter. The female flowers remain enclosed within the bud and have a reddish tip.
When the weather is windy, the pollen is spread into the surrounding area - this can lead to severe symptoms for those suffering from hay fever in February and March. However, bees are all the happier about the early food source in the year.
Flowers in keywords:
fruit
For thousands of years, hazelnuts have been valued by humans and many animals as a tasty and nutritious natural gift. Like the common hazel, the corkscrew hazel also develops the typical nut fruits from September, albeit to a somewhat lesser extent. In addition, the nuts remain smaller, are not quite as tasty and their consistency is not as crunchy and tender, but rather woody.
Therefore, the corkscrew hazel is mainly used as an ornamental shrub. If you would like to harvest a lot of your own hazelnuts, you should rather rely on a common hazel. A corkscrew hazel takes about 10 years to ripen.
Fruits at a glance:
Which location is suitable?
The corkscrew hazel prefers a sunny to partially shaded spot in the garden. The sunnier the location, the more vigorously it thrives.
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What soil does the plant need?
For the corkscrew hazel, the soil should be nutrient-rich and humus-rich, well drained and moist. The pH value should be in the high range. In addition, the corkscrew hazel likes it warm on the feet - so it is advantageous if the sun can penetrate its base and the location is relatively close to other trees or the house. In general, however, the corkscrew hazel is quite tolerant when it comes to site conditions.
When planting grafted corkscrew hazels, it is important to place the root ball a little deeper in the planting hole so that the grafting point is underground. In this way, you avoid the growth of straight wild shoots, which disturb the appearance of the characteristically winding branches and, above all, quickly overgrow it. With ungrafted corkscrew hazels you do not need to heed this measure, but such specimens are hard to come by.
To remember:
The right planting distance
However, the corkscrew hazel has to keep a little distance to neighboring plants so that its flat, extensive root system can develop well. In addition, it looks very good as a solitaire. You should leave a radius of about 2 meters around the bush.
How do I plant correctly?
If possible, you should not transplant a corkscrew hazel. Digging up and moving to another location means a lot of stress for the shallow-rooted shrub, which should be avoided as much as possible. However, if you want or have to move it for reasons of space or neighborliness, you should only do this with a young specimen. The shrub should not be older than 5 years, otherwise it will have become too established at its location.
The best time to transplant is early spring before the leaves emerge. In addition, there should be no frost.
When transplanting, it is important to generously dig up the extensive root system. This is of course a lot of work, but the less root mass you cut off the corkscrew hazel, the better. The new planting hole should be twice the volume of the root ball and be bedded with drainage made of sandy soil. After inserting, fill the hole with humus-rich soil, tread firmly and water vigorously. A support pole for stabilization is recommended.
To compensate for the inevitable loss of roots, you should also cut back the shrub a little.
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Pour corkscrew hazel
A corkscrew hazel outdoors only needs a separate watering when planting and during longer dry periods in summer. Then you should water them thoroughly once.
If you keep them in the tub, regular watering is of course essential.
Fertilize corkscrew hazel properly
Since the corkscrew hazel needs a lot of nutrients, it is advisable to give it some extra energy from time to time. For a specimen in the field, good, mature compost is best, which you can easily work into your planting ground in spring.
A corkscrew hazel in a tub should be given a liquid fertilizer about every 2 weeks during the growth period from March to September.
Cut corkscrew hazel correctly
The corkscrew hazel usually does not need pruning - after all, it is valued for its characteristic growth. It also thrives better and more willingly when allowed to grow in peace. However, if you plan to transplant the shrub in its first few years, pruning is recommended after the transplanting procedure.
Another exception is when wild shoots form from the planting ground. This happens quite easily, especially with refined specimens. It can also occur in ungrafted individuals, but is much less common. If you just notice shoots that shoot into the shrubbery, this is by no means a harmless aesthetic disruptive factor - because the wild shoots are very vigorous and can quickly overgrow the mutated branch structure.
In order to preserve the characteristic appearance of your corkscrew hazel, you should quickly grab the scissors in this case. Place them as close to the ground as possible on the wild shoots growing out below and be thorough when identifying them.
A radical pruning of old, bald specimens is also possible.
Cutting rules at a glance:
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Propagating corkscrew hazel
Propagating a corkscrew hazel is not entirely trivial because it is usually a grafted specimen in gardens. The rooting of grafted plant parts is therefore somewhat difficult. However, you can try the cuttings or the sinking method.
cuttings
Cut a young, non-woody shoot that has about 4 to 6 leaves from the upper, inner crown of the bush. Ideally, make the cut directly below one eye. Remove all leaves except for the top two and place the prepared cuttings either in a planter with a peat-sand mixture or in a glass of water. The location should be bright and warm.
lowering
The thin, flexible branches of the corkscrew willow, which are attached far down, can also be used to lay lowers. Find a shoot that is growing outside and is as young as possible (which of course should not be a wild shoot) and place it in a previously dug notch in the ground. Fix it with a metal hook at the curved target growth point. Then straighten the shoot tip upwards and stabilize it with a wooden stick. A wound incision at the site of attachment may be helpful.
pests
Apart from the harmless disease that gives it its typical appearance, the corkscrew hazel is largely immune to disease. However, it can certainly be infested by species-specific parasites. This includes above all the hazelnut borer, which is also a nuisance for the common hazel. It destroys the harvest by laying eggs and developing larvae in the fruit. The nuts are then perforated accordingly.
Fighting the weevils is relatively difficult. Chemical insecticides against the parasite are not permitted in private gardens. If there is an infestation, you should first collect the adult beetles by hand or shake them off the bush and release them far away from your garden. The infested nuts are also collected and disposed of as thoroughly as possible, preferably incinerated. To prevent the hatched larvae from surviving in the ground over the winter, cover the planting ground with a garden fleece in autumn.
To prevent this, you can also hang a glue ring in the bush.
tip
If you want to save yourself the frequent removal of wild shoots, when you buy a grafted corkscrew hazel, opt for a specimen with the Turkish tree hazel as a rootstock. Such variants are less prone to developing wild shoots than those based on common hazel. If you would like to get a high-stemmed corkscrew hazel, there are also variants grafted onto tree hazels.
sorts
A special cultivated form of the corkscrew hazel is offered in the plant trade, especially in the form of Corylus avellana 'Red Majestic'.
Corylus avellana 'Red Majestic'
The variant, also known as "red-leaved corkscrew hazel" or "blood corkscrew hazel", is definitely worth considering as an alternative to the normal Corylus avellana - because, as its trivial names suggest, it has a very special appeal with its deep dark red foliage. The male catkins of this variety also show a reddish colour. As with the normal corkscrew hazel, the flowering period is in February and March.
The growth of the red-leaved corkscrew hazel is somewhat smaller than the wild species and the green-leaved corkscrew hazel - it only grows to a height of around 2.50 m, but because of its bushy branching it is around 3 m wide.