The fan cotoneaster grows decumbent and spreads its branches horizontally. The groundcover is hardy and also tolerates drought and heat.
The botanical technical name Cotoneaster horizontalis already indicates that the fan cotoneaster is a deciduous woody plant. The shoots, which are up to 1 m long, spread out horizontally and in a fan shape. This turns the ornamental tree into a wonderful ground cover.
Medlars and cotoneasters are among the most popular bird pastures in the garden. The trees and shrubs usually form tall shrubs or small trees of up to 15 m. However, there are also small species that are more suitable for low-growing plant concepts. One of them is the fan cotoneaster (Cotoneaster horizontalis). It grows to a height of just 50 to 100 cm and is therefore ideal for short plant arrangements.
Cotoneaster in the garden
Cotoneaster horizontalis is often found as a gap filler in borders or on the edge of trees. The fan cotoneaster is also suitable for upgrading bare spots in the garden. They are excellently concealed by the prostrate wood. The decorative red fruits of the ornamental shrub pepper the green carpet of leaves after the fruit has ripened in late summer, possibly even into December. The plant's autumn foliage, which comes in an orange-red color that matches the season, is also particularly attractive.
The dense branches of the shrub are a wonderful hiding place for birds and small wild animals. They also like to feed on the red fruits of the shrub, but be careful. Although cotoneasters belong to the pome fruit family along with apples and pears, they are poisonous to humans. Therefore, only plant Cotoneaster horizontalis out of the reach of children.
One garden concept that particularly benefits from the culture of the cotoneaster is the rock garden. Here, the ornamental wood gives stone walls and gravel beds an original color accent. But Cotoneaster horizontalis also spreads very decoratively on conventional slopes, embankments or walls. On the wall of the house, a decorative hem can be placed around the foundation for large-scale planting. And also in the plant wall the fan cotoneaster occurs asFaçade greening really comes into its own.
» Tip: Cotoneasters are also very popular as bonsai. The low growth height of the tree allows good shaping with just a few cuts.
| Cotoneaster (Cotoneaster horizontalis) | |
|---|---|
| Growth Speed: | 10 - 15 cm a year |
| Growth: | 80 - 100 cm |
| Growth: | 150 - 200 cm |
| Root system: | Shallow roots |
| Location: | Sun to partial shade |
| Floor: | normal, permeable, acidic to alkaline |
Cotoneaster - location and planting process
There is a reason why the fan cotoneaster is often cultivated as a bonsai. Because the ornamental tree originally comes from East Asia, where it mainly grows in the cool, damp forests of Japan and China. Accordingly, the wood also wants a freshly moist location in the garden in the light semi-shade, which is reminiscent of the location terrain of the area of origin. A sandy-loamy or sandy-gravelly soil with an acidic to neutral pH between 5.5 and 7 points is ideal.
Winter protection is not required for Cotoneaster horizontalis. Due to its origin, the plant is used to very cold altitudes of up to 3500 m. The cold resistance of the fan cotoneaster is therefore surprisingly good and reaches down to -35 °C. Only a frost-free period of 14 per year must be guaranteed.
➔ Planting the cotoneaster - this is how it works
- You can plant the cotoneaster in both autumn and spring. However, autumn planting is recommended, as this gives the tree enough time to establish itself at the site before the next growth phase.
- Basically, ordinary potting soil is completely sufficient for Cotoneaster horizontalis. For a good soil optimization, however, it makes sense to enrich the substrate with some gravel or sand. Since the wood does not like waterlogging, gravel drainage is also recommended. This care measure is not necessary in the pot. Make sure here, however, that the saucer has drainage holes for good water drainage. In addition, the planter should offer the ornamental tree enough space for root growth. Wide pots and bonsai pots are best suited for the shallow-rooted cotoneaster.
- Cotoneasters grow relatively slowly. A planting hole of one and a half times the diameter of the root ball is therefore completely sufficient.A sufficient planting distance between the individual plants is more important. Since Cotoneaster horizontalis is a flat-rooted plant, a distance of at least 50 cm should be maintained. Furthermore, a topsoil density of at least 41 cm must be ensured so that the wood develops well.
Watering and fertilizing the fan cotoneaster
Even if the fan cotoneaster prefers moist soil, it can cope with drought at times. In order to avoid longer dry periods in summer, however, it is advisable to apply a layer of mulch in the root area. It protects the plant from drying out and also keeps weeds away. Overall, moderate but regular watering is indicated. This also applies to the winter months, when you should also water Cotoneaster horizontalis on frost-free days.
The best way to fertilize fan cotoneasters is with a liquid fertilizer for ornamental trees. Fertilizer granules are also conceivable. Overall, the ornamental tree is not particularly hungry for nutrients. It is sufficient if you supply them with fresh nutrients every two years in spring. An exception are bonsai cultures, which have to be regularly treated with a special bonsai fertilizer.
Pruning and propagating fan cotoneaster
Due to its low annual growth of just 10 to 15 cm per year, a standard garden cotoneaster rarely needs pruning. However, a final growth width of up to 2 m suggests occasional topiary. Minor corrective cuts can be made if the plant begins to overhang the bed or borders too much. Otherwise, thinning out the shoots in spring will do.
➔ Cut fan cotoneaster as bonsai
Pruning is a bit different if you keep Cotoneaster horizontalis as a bonsai. Very specific pruning measures are required here in order to develop the wood into a bonsai tree.
➔ Pruning
Young bonsai in particular must be pruned from the start in such a way that they change from a shrub to a tree shape. This is achieved by cutting back the young trees by half each year.
➔ Topiary
For shaping, the shoots of the cotoneaster bonsai are cut back to two knots. This encourages branching into a compact treetop. Keep track of the bonsai's final tree shape over the years here.
➔ Taper Cut
In order to regularly rejuvenate the bonsai, also remove all dead and older branches in spring. It should onlyShoots remain that you need for the further wiring of the bonsai. On Cotoneaster horizontalis, these can be all up to three-year-old shoots. They are still relatively easy to shape and can therefore remain on the wood.
➔ Propagation by cuttings or offshoots
Each cut on the cotoneaster can be used to take cuttings.
- Cut off he althy shoots approx. 10 cm long and remove the lower pairs of leaves.
- Put the shoot pieces in a container with potting soil and water it well.
- Putting a glass or plastic bag over the container can help to prevent dehydration. In this way, the cuttings usually root after a few weeks.
As an alternative to the propagation of cuttings, Cotoneaster can also be easily propagated via offshoots. To do this, select a shoot that is close to the ground and fix it to the ground with a stone or wire hook. In order to root quickly, the offshoot should be covered with soil down to the tip of the shoot. With regular watering, rooted sinkers can be separated from the mother plant and replanted after about two years.
Damage to the fan cotoneaster
Pests such as the red spider mite or scale insects occasionally tamper with the cotoneaster. An infestation by spider mites can be recognized by the fine cobwebs that are mainly found on the leaves and leaf axils of the tree. Scale insects, on the other hand, leave their sticky excretion products, the so-called honeydew, on the leaves of the cotoneaster. Both pests can be counteracted with natural insecticides such as nettle or garlic broth. Furthermore, you can use beneficial insects as natural enemies of the pests.
➔ Fire blight is extremely dangerous
In terms of plant diseases, Cotoneaster horizontalis is threatened by fire blight, among other things. It is a bacterial disease caused by the bacterium Erwinia amylovora. In addition to cotoneasters, it also attacks pome fruit plants with above-average frequency. So if you also have apple or pear trees in your garden, you should be particularly vigilant here.
» Warning: Fire blight is notifiable in Germany! Since the causative pathogen is extremely aggressive and sometimes threatens entire plant populations, you have to treat affected plants according to very strict quarantine measures. The quarantine zone can be up to 5 m. Responsible for the execution and information are regionalDepartments of Agriculture.
You can recognize the fire blight by shriveled fruits and withered leaves. They turn brown or black in the course of the disease, so that they actually look burned. For the prevention of fire blight there are some antibiotic agents such as streptomycin and potassium alum (LMA). However, if an infestation has already taken place, the gardener may have no choice but to properly dispose of the plant.
➔ Treat powdery mildew and plant rust easily
Fungous diseases such as powdery mildew or rust fungi can be combated much more easily on cotoneasters. In the case of powdery mildew, a distinction is made between real and downy mildew. Powdery mildew is indicated by a white coating on the upper side of the leaf, while downy mildew manifests itself on the underside of the leaf. Rust fungi, on the other hand, cause orange-yellow to brown pustules on the shoots and leaves of Cotoneaster horizontalis.
In both cases, appropriate fungicides help to contain the infestation quickly. Before doing so, however, you must generously remove and dispose of all infested parts of the plant. Please do not throw the parts of the plant on the compost, otherwise the harmful fungi can spread further. Instead, separate disposal in household waste makes sense. For follow-up treatment, as well as for prevention, you should then ensure good soil ventilation. Keeping the roots sufficiently moist can also help with powdery mildew. This strengthens the plant and makes it difficult for fungal pathogens to gain a foothold.