How to Care for Japanese Maple Bonsai – Guide

In this article, we will explain everything you need to know to properly care for your Japanese maple bonsai. The Japanese maple bonsai could be classified as medium-difficult to care for, but if you follow all the tips we will give you can always have it in perfect condition.

The Acer genus belongs to the Aceraceae family and is represented by about 150 to 200 species. They inhabit the temperate zones of the northern hemisphere, mainly in Asia.

Due to the great differences between the various species (color of leaves and trunk, types of leaves, etc.) and the fact that many of them are natural hybrids, their classification is somewhat complicated and throughout the history of botany, there have been many confusions and discussions that continue today.

In general, we could say that the Japanese and Oriental species are usually small trees with more beautiful and delicate leaves than the American and European species.

How to Care for Japanese Maple Bonsai

Here you will learn everything you need to know about how to care for Japanese maple bonsai correctly. You may also be interested in our other guide on How to Care for Bonsai Tree, it is a general guide for all bonsai.

Care for Japanese Maple Bonsai – Location

Japanese maple bonsai should be grown outdoors all year round but avoiding direct sun, especially in summer. Its leaves are easily burned by the sun or dry wind. The optimal place could be a cool area of penumbra or semi-shade with a lot of light.

It tolerates cold well, we must watch out for hard frosts, below 14°F (-10°C), this does not mean that we should protect it inside a greenhouse or the house, it needs to feel the winter cold passing and allow spring to cause the buds to awaken in repose. If we protect it from the cold and the temperature is too mild or too warm it may sprout prematurely, which will weaken it.

Once it has found its most suitable location, it is not advisable to move it from one place to another because it suffers from being moved, especially if it is moved frequently.

Care for Japanese Maple Bonsai – Watering

Watering should be done every time the surface of the soil dries out, but thoroughly, that is, until abundant water comes out of the drainage holes, avoiding permanent waterlogging of the soil to avoid excess moisture that rots its roots.

This bonsai does not tolerate drought and its roots need regular and permanent humidity. We must prevent the soil from becoming completely dry because it is very sensitive to excess heat and dry air, which quickly causes the leaves to wilt or their tips to burn (brown edges).

It is advisable to use a watering can with holes as fine as possible so that the water penetrates the soil better and gently.

Do not spray the leaves or artificially maintain an excessively humid environment because of the risk of fungus. In any case, if you decide to spray, do so with great caution and as long as you have not forgotten to apply the corresponding spring and autumn fungicide treatments. Never do it when the tree is in bloom because its flowers will wilt prematurely.

Care for Japanese Maple Bonsai – Soil

A good soil mix for a maple could be a slightly acid soil with 20% coarse-grained sand or equivalent material (volcanic soil, etc.), 20% peat and 60% mulch, or any of the prepared acer palmatumlas mixes that can be found in specialized stores, such as Bidama. In any case, it must be a mixture with excellent drainage (Order it here).

The mixture should be rather acidic (pH around 5.7). To control the pH correctly you should use a pH meter like the one we use (Order it here).

Do not forget that the soil used should always be new and clean and never reused from other crops to avoid contamination (fungi, diseases, pests, etc.) that could have affected other trees.

Care for Japanese Maple Bonsai – Fertilizing

Fertilize frequently with a quality organic fertilizer, especially during the period of vigorous growth, i.e. from spring to autumn. During the winter and the hottest part of the summer, you should reduce the amount of fertilizer because these are times with little or no growth.

We can help to reduce the size of the leaves, in addition to a good outdoor exposure to full sun with the supply of fertilizers richer in phosphorus (P) and potassium (K) than in nitrogen (N) to not encourage the development of its leaves, and also encourage fruiting.

For the correct care of Japanese maple bonsai trees we use this brand of specific fertilizer for bonsai (Order it here).

We must not forget that we cannot:

Fertilize a repotted tree, we must wait for it to sprout.

Water a tree grown outdoors after a frost or when there is a risk of frost.

Repotting Maple Bonsai

During early spring, every 1 or 2 years due to a large number of roots it develops, just before the beginning of the year’s sprouting, when the buds are swollen, although in old specimens it can be repotted every 3 years. It is very important for the correct care of the Japanese maple bonsai to repot as mentioned above.

During repotting, it is advisable to clean up any rotten roots and prune unwanted branches to reduce their crown. If the root pruning is very large, it is advisable to remove leaves in the same proportion as the roots removed. In case of doubt about the number of roots to prune, a sure trick to avoid damaging the tree is to leave 1/3 more root volume than the aerial part (crown).

It is not mandatory, but if we use rooting hormones with fungicide we will facilitate the success of the repotting by stimulating root development. You should be as quick as possible during repotting and prevent the roots from drying out by being in contact with the air for too long (Order it here).

How to Prune Japanese Maple Bonsai

The most suitable time for pruning branches is after leaf fall, during autumn or winter. For the correct care of the Japanese maple bonsai, we must use the right tools to avoid damaging it (Order it here).

Its rapid growth will force us to pinch it 2 or 3 (or more) times during the summer, making the pinching acer palmatum on the new shoots, reducing them to 2-3 leaves, and always when these have matured, never before, to balance its vigor.

If you just want to maintain its shape, you should immediately remove unwanted new shoots as soon as they appear.

Withered leaves should be removed to prevent fungus and unwanted or dry branches can be removed at any time.

Never prune drastically if the tree is not healthy and vigorous. It is important to use a pruning cutting paste after cutting for a correct care of the Japanese maple bonsai (Order it here).

In addition to pruning for shaping, pruning should be done to achieve a structure that allows light to reach all the branches and all the leaves to photosynthesize.

There should be a minimum time interval between branch pruning and repotting so as not to accumulate too many aggressive operations at the same time, for example, 3 weeks.

Finally, remember that pruning, pinching, or defoliation should only be done if the tree is healthy.

Wiring Maple Bonsai

The wiring of Japanese maple bonsai should preferably be done during the winter and early spring, taking advantage of the fact that it is leafless. However, it can be modeled by planning acer palmatumpodas in successive years.

It is advisable to wire with paper-covered wire so as not to damage the bark of the branches and trunk, as this is very easily damaged. You should also be careful with the branches due to their fragility and you should watch the wire marks on the bark due to the rapidity with which they fatten and grow, generally, the wire should be removed during the autumn of the same year in which it was wired or at the moment in which the appearance of marks on the bark is going to begin.

Most Common Diseases and Pests

Maple is a fairly hardy species, even to changes in weather conditions and atmospheric pollution, but it is especially sensitive to:

Maple leaf gall mite: microscopic mite that appears in early summer and sucks sap. There is no effective treatment for this pest, although it has no detrimental effect on the tree. The only thing we can do is remove the affected leaves.

Fungi: especially in the roots, which obstructs the ducts that transport the raw sap, causing the death of the tree, being impossible to combat. Fungus problems are easily solved by watering properly, i.e. allowing the soil surface to dry out between watering, not spraying the leaves, and carrying out appropriate preventive fungicide treatments in spring and autumn.

Aphid: like the mealybug, it is a sap-sucking insect, generally brown or black, grouped on tender shoots and in very dense colonies protected by ants that collect the honeydew secreted by the shoots.

Where to Buy Japanese Maple Bonsai?

If you can’t get your Japanese maple bonsai here is where to get it from seed. It is an interesting process to raise it from seed and at the same time you will learn a lot.

We hope this article on how to care for Japanese maple bonsai will be helpful.