Growing Bonsai from Ground Layering

This technique is similar to taking cuttings to the extent that it is based on the principle of producing spontaneous root growth from a shoot. But in layering, rooting takes place without the cutting being separated from its parent. Roots develop after a part of a branch is buried in the soil or in other medium conditions that favour rooting. This is a gentler method of propagation, since the cutting is not severed from its parent until it is well rooted.

There are many different methods of layering. Here are only the most familiar. A broad distinction can be made between ground layering, where a branch or shoot is bent down to the ground, and air layering.

Ground layering

Here roots grow where a branch or shoot is in direct contact with the earth. This type of propagation is considered spontaneous, insofar as it is often found in nature on plants with trailing branches, such as wild rhododendrons.

Simple ground layering

This technique is most like the natural phenomenon. A low branch is bent down to the ground, where it is held in place by a wire hoop. The part of the branch touching the ground is lightly covered with earth, the rest being supported by a stake. To stimulate rooting, the buried part should be brushed with hormone rooting powder and its bark lightly scored.

Simple layering is usually carried out during the dormant period, so roots should appear in spring. The layer can be severed from its parent in autumn, but, to be quite sure, it can always be left till the end of the following winter.

To root a layer in a pot, just bend the parent branch into a pot, then proceed exactly as above. As some branches might not be inclined to sit in the pot in the way you would like them to, particular care should be taken to secure the potential layering to stop it 'springing' from the pot.

Stooling

This is only possible with shrubs which tolerate heavy pruning. This method involves drastic pruning, cutting the bush right down to its crown before the new season's growth starts. Then mound or cover the base of the plant with soil and in spring, when the shoots develop, the roots will have started to form at their base, above the crown. The mound can be cleared and the layers exposed and planted out during the course of the following winter. Root development can be noted at this stage and if it is inadequate, the layers should be left attached to their parent for a further year.

Chinese layering

In this method, the branch is stripped of its leaves, leaving all the eyes (leaf buds) intact and laid along the ground and covered with earth. The leaf buds will then develop vertical shoots, which sprout from the ground to form rooted layers. To separate them, just cut the parent branch between the shoots. This should be done during the winter after the shoots sprout.

Serpentine layering

This is a variation of the simple layering method. Instead of being buried once, the branch is arched and staked several times, forming a succession of undulations. Otherwise, this method is exactly as for simple layering with the lower parts pegged in contact with the soil and scored and dipped in hormone rooting powder. Severing the cuttings is again as for simple layering.

Of the methods described, simple layering is recommended as the best way of producing a bonsai, since it allows you to choose the style you want. It is possible to select a particular branch for its shape. Make sure that the aerial part of the layer is well supported, otherwise it could become deformed while the roots are forming.

Where simple layering takes place in a pot, a method which avoids the shock of transplanting, the cutting should be regularly watered before and after it is separated from its parent.