Silk tree, sleeping tree, silk acacia – care, pruning and wintering

In order to ensure optimal growth conditions for the silk tree, the location should be chosen carefully. Sunny places or areas in the garden that are in partial shade have proven to be advantageous. In addition, the chosen location should offer some protection from the elements, such as wind and frost; especially at a young age, the tree shows sensitivity to frost. The silk acacia thrives best outdoors on a house wall that faces south. However, the vigor of the plant should be taken into account. With good care, the silk tree can reach a height of up to eight meters. An expansion in width is possible up to four meters. Therefore the location should not be too close to the house wall, so that the tree can optimally unfold in all directions. Alternatively, cultivation in the winter garden is also possible.

The silk acacia thrives in many different soils. Mixtures that have the following properties have proven particularly useful:

• fumes
• locker
• permeable

The substrate used should be such that the formation of waterlogging is avoided. In addition, a high proportion of sand in the soil leads to the formation of much more robust trees that can survive the wintering phase more easily. In contrast, clay soils are generally not suitable for cultivating silk acacias. The very heavy soils favor waterlogging. – The development of root rot can be the result.

Care of the silk acacia

Balanced watering is particularly important for the plant to develop properly. In summer, watering should be abundant and regular, while in winter the fluid intake is significantly restricted. Basically, the substrate must always be slightly damp; it is essential to avoid drying out of the root ball. However, excessive water intake, which can lead to waterlogging, should also be avoided. Especially with very young plants there is a slight risk of overwatering, which is why they must be cared for with particular care. Fertilization takes place exclusively during the growth phase. Between March and the end of July, fertilizers can be applied every two weeks.

Since the silk acacia grows very quickly, additional supports should be added from the beginning. These supports must be as straight as possible, since an arched growth cannot be compensated for later.

Cultivation in the bucket

The silk tree can also be kept in a bucket. However, the plant must not have become too big with such cultivation. Ideal irrigation is of particular importance when it comes to keeping them in a bucket. The plant reacts to persistent drought by rolling up the leaves. With this measure, the silk acacia tries to prevent further moisture loss through evaporation. In this case, the amount of watering needs to be increased. In order to optimally overwinter the silk acacias grown in the bucket, they should be moved to a cold room and watered moderately. Greenhouses or cold houses are particularly suitable in this context. If, on the other hand, the silk acacia that is cultivated in the bucket is to overwinter outdoors, additional winter protection is necessary. For this purpose, the plant is carefully wrapped with fleece. So that the sleeping tree is not exposed to the intense rays of the winter sun, a shady area close to the house wall should be chosen for wintering.

Targeted pruning of the plant

There are various options available for cutting the silk tree in a targeted manner:

• Cut back young plants to influence their growth
• Topiary in old plants
• Radical section of dead plants

Young plants should be pricked several times so that they branch better. How a silk acacia is pruned depends on whether it is to be grown as a shrub or as a small tree. Sleeping trees in the tub should usually develop a beautiful bush-shaped shape, then the young plant should be pruned several times in the shoot tips so that it branches well.

The further pruning measures depend primarily on the decision whether the plant is to be cultivated as a tree or as a shrub. Silk acacias that are supposed to grow as a tree should be allowed to grow up quickly. To do this, the lower branches are removed. The crown then develops as a semi-round, broadly tapering and flat structure that resembles an umbrella. Every cut between the leaves stimulates a new shoot.

However, the accelerated growth can cause problems if the plant is grown indoors. If they are kept too warm with little incidence of light at the same time, silk trees tend to ginger during the winter months. During this process, they grow suddenly upwards, with only very thin shoots being formed. To prevent this phenomenon, the plant should be grown in spring and taken outdoors as early as possible and left there, preferably between May and October.

If a specimen has already developed into gelatinization, the plant should be cut back radically to half its height. The cut is made directly over a sleeping eye. Such a radical cut is usually well tolerated by the silk acacia; however, the plant must not be exposed to the blazing sun afterwards. Usually the plant becomes stronger after the treatment and develops numerous strong shoots

Older specimens are mainly cut to get them into shape. In this context, early spring has proven to be the ideal time for targeted pruning. The silk tree can withstand a cut that extends into the old wood without any problems.

This is how wintering works

The silk acacia is particularly sensitive to frost in the first years of life. The evergreen plant loses its leaves during the cold season; Adequate protection against cold and frost is necessary, especially in the first three years, in order to avoid damage. For this purpose, it has proven useful to use rotted leaves for isolation. Care must be taken that the leaves show no signs of disease. Above all, dry leftover leaves should be used so that they do not stick together from the start. Alternatively, fir branches that are arranged around the tree are suitable. In addition, the trunks of the young plants need winter protection, as the rays of the winter sun often have a very strong effect.
For potted plants that are kept on the balcony or terrace, the following aspects must be observed when wintering:

• Temperatures between 5 and 15 ° C
• sufficient brightness
• water sporadically
• Prevent the root ball from drying out

A cold house is best for wintering. Alternatively, the warm overwintering can also be successful. The sleeping tree should then be sprayed with water when the humidity is low. In the case of warm wintering, the addition of a fertilizer every two weeks has proven itself.
Note: The warm overwintering probably leads to the shedding of the leaves; however, after a targeted cut in spring, the plant sprouts again.

Propagation and sowing

The silk acacia is particularly easy to reproduce using seeds. These are first soaked in water for two to three hours before use. The temperature of the water should be 28 ° C. The seeds are then ready to use. The plant pots are filled with special potting soil. Now the seeds can be placed on the substrate; after pressing, these are only lightly covered with earth. In order to germinate optimally, the seedlings need a temperature between 20 and 25 ° C; for this purpose it has proven useful to cover the pots with cling film. It is best to use a small greenhouse. The seedlings must be regularly supplied with water during cultivation. When the young plants have formed a few leaves, the plants can be pricked out individually in pots.

Diseases and pests

Most illnesses arise from neglect of care. If the silk acacia receives too little light, the plant sheds its leaves. Then the location has to be changed. If, on the other hand, the sleeping tree rolls up its leaves during the day, the plant suffers from a lack of water. If too much water is given, waterlogging can lead to root rot.

In addition to these diseases, the silk tree was sometimes attacked by guilty lice. The infestation is easy to recognize based on a characteristic damage pattern:

• Pustule-like shields on the leaves, either cup-shaped or lid-shaped
• crust-like coverings
• sticky excretions of honeydew
• Disabilities
• Growth inhibitions

So that there is no infestation by scale insects in the first place, beneficial organisms can be promoted as a preventive measure. These include, for example, ladybugs, parasitic wasps and earwigs. In addition, the parts of the plant infected with shields should be brushed off regularly. This is particularly easy to do with a toothbrush. In addition, various oil-based sprayings help with acute infestation. Paraffin oils or rapeseed oil are mainly used in this context.

Information on naming
The silk acacia is often referred to as the “sleeping tree”. The reason for this naming lies in the natural spectacle that the plant offers every evening: the leaves curl up and the flowers collapse. During this process, the tree gives the impression that it is preparing to sleep. This phenomenon has often been used to encourage children to go to bed in the evening.

Conclusion
The silk tree is certainly one of the elegant plants in home gardens that look very elegant due to their decorative flowers. With a little experience and a sure instinct, the right watering behavior must be trained when keeping the tree; then garden lovers can enjoy the imposing plant for a long time.