If you want to bring a bright bold color into your home or garden, the Japanese Maple is a great choice for bonsai. With yellows, greens, crimson, pinks, orange and brilliant reds, the Japanese Maple put on a flashy show every autumn.
All about Japanese Maples
Japanese Maples (Acer palmatum) is found across much of China, Korea and Japan, and indeed the rest of the world. They thrive in mountainous and woody areas, where they receive dappled shade and wind protection. Most are upright and develop multiple trunks. There are a number of varieties, and all are suitable for bonsai. Trees in the wild can grow to 45ft tall.
Types of Japanese Maples for bonsai
There are several cultivar options. Red-leaf cultivars are very attractive, with a feathery type of structure. The reds include variations of pink and orange as well. Rough barked cultivars have aged appearance even as young plants, and develop a yellow shade leaf during autumn. These leaves are sometimes considered too large for bonsai, but with trimming you may be able to encourage smaller leaves to dominate. The Trident Maple has a spectacular autumn color is use commonly used as bonsai.
Dwarf varieties of Japanese Maple as a bonsai
There are also dwarf varieties which are very attractive but can bring challenges. They are prone to weakness and are base dominant. This means careful attention is needed to redirect energy which can be done with wire and careful pruning. Dwarf varieties will not tolerate extreme temperatures and dappled shade is a must. Kashima and Yatsubusa might be good choices for beginners.
Japanese Maple bonsai likes and dislikes
Japanese Maples like a light, well-drained soil which includes sand. What you select as a grit or gravel component will impact the look of both the roots and branches. This is because smoother or smaller gravel particles allow root tips more movement which creates stronger and undivided roots. Roots will divide to move past coarser soil. In each case, the appearance is echoed in the branches above. You might wish to mix smoother, smaller gravel with some larger pieces. The recommended soil to gravel mix is 60%- 40%.
Watering Japanese Maple bonsai
Like other plants that are natural to woodland areas, Japanese Maples like being damp and having a cool root system. Ensuring your bonsai has adequate shade will help it retain moisture and offer protection from hot sun, and also drying winds. Try to maintain dampness, but avoid overwatering. Do a soil test to check for dryness instead of watering as a specific routine. Water with a gentle spray or by the emersion method. Ventilation under as well as around the bonsai pot is also helpful.
Repotting Japanese Maple bonsai
When your Japanese Maple bonsai is ready to be transplanted and has a strong collection of roots, take the plant out of its pot. Using bonsai tools, remove between half and one third of the rootball. Young trees will be repotted every couple of years while older trees will require repotting at around the three year mark. Watch for declining growth as a trigger to prompt replanting. You will see dieback on finer twigs and notice that water is slow to drain.
If you have one of the red leaf varieties kept in a pot, you may note that exposure to cold weather causes leaves to appear pale. This is generally considered undesirable and also indicates your plant is experiencing a degree of stress. Bring the plant indoors or into a greenhouse and provide it with some extra feed.
Root rot in Japanese Maple bonsai
When conducting repotting, examine the roots for root rot. You will see roots which are mushy, and discolored. The plant may also give you signs that there is root rot. Look for indented wrinkles in straight lines along the limbs. If you have a severe case of root rot, one solution might be to plant the tree in a gravel based soil mix, within a large wooden box. Keep the box raised from the ground to encourage airflow. It might be helpful to think of the tree as a large cutting that needs extra support until roots appear.
Bugs and Pests
Unfortunately, there are a range of pests and diseases that can affect your Japanese Maple bonsai. Mildew and mold will appear like whitish-grey areas or fuzzy grey spots on leaves and twigs. Ensuring your plant is in a well-ventilated area can help prevent these problems. You might also encounter aphids and scale insects- they just love getting stuck into new and young leaves. Suitable insecticides can be bought or made.
Japanese Maple bonsai timeline
- Spring – buds will swell- consider repotting
- Summer – protect by covering them with a shade cloth or netting, pay attention to watering and fertilize during late summer
- Autumn – enjoy the colours, remove fallen leaves
- Winter – protect from extreme temperatures, which could include relocation to an area protected from frost and winds
Tips to help your Japanese Maple bonsai
Styles to consider include informal upright and twin branch. Some very effective and dramatic looks can be achieved by growing roots over a rock. Japanese Maples also lend themselves well to being grouped, meaning multiple plants are set in the same pot. Arrange the young trees to create the appearance of a grove and seek to establish some variety in the height and shape of the trunks. Do not leave wire on the tree for more than six months, and remove as soon as you see wire causing any biting on the bark.
Advice on growing a Japanese Maple bonsai
Maples love to be placed within a wooden box. Wood is a wonderful organic material that can breathe, is not affected by temperature as much as clay, plastic or ceramic. Japanese Maples also look great in glazed pots in white or light green. Avoid colours that are loud or bold. Unglazed pots also work well and have a more natural tonal range. Do not try to train into the styles known as ‘windswept’ or ‘driftwood’.
The bottom line: These trees are generally strong and rugged, with an attractive bark that can look like it is older than it really is. It is a versatile plant that looks good in most styles, and can be located in the garden, inside or in a pretty patio pot.