Acer palmatum, commonly known as Japanese maple , is a species of woody plant native to Japan, Korea, China, eastern Mongolia, and southeast Russia. It is a deciduous shrub or small tree reaching heights of 6 to 10 m (20 to 33 ft), rarely 16 metres (52 ft), for its exotic beauty it is planted in gardens around the world. In this article we will learn all about how and when to prune a Japanese maple, plus some tips to take care of it.
Note: Please note that the advice given here is general, this blog is consulted from many countries in the world, with totally different characteristics, what not all tips will be adapted in the same way in all cases. Once you finish reading the article it will be necessary to analyze all the information and apply what you have learned in the best way. If you have any questions, remember that you can contact us to make your inquiries.
Table of Contents
1. How to recognize a Japanese maple?
There are hundreds of species of maples and as many subspecies. If that has added up the different habits, it can be really difficult to recognize a Japanese maple from any other type of maple.
Each type of maple has one or several badges, these can be the color or size of its leaves, the bark of its trunk, etc.
Undoubtedly in the Japanese maple the hallmark is the shape of its leaves. It is known for very distinct lobing of the leaves, so much so that they almost appear to be compound leaves. However, you will note all lobes of this leaf still originate from a single point on the leaf stock and have no stems of their own.
2. Care of japanese maple tree
Pruning is one of many cares that a Japanese maple needs to be healthy, strong and beautiful. In this section we will briefly see the most important care.
- Soil: Japanese Maples require well-drained soil and can not tolerate soggy-wet (clay) sub-soils. This is critical to prevent winter injury. Before planting, loosen the soil, and incorporate a generous amount of organic matter, such as sphagnum peat moss, or compost and perlite into a minimum 5’ diameter area.
- Sunlight: Japanese Maples thrive in full sun to part shade. If you are planting a red Japanese Maple, a good balance of full sun with some shade for protection from harsh summer sunlight is recommended to prevent sunburn and tip browning during mid to late summer. Japanese Maples will grow in partial shade, however they may not develop their characteristic color and may remain greenish-red.
- Watering: Water deeply twice a week; water more often if it is a newly planted tree or a container-grown tree.
- Mulching: Mulch protects the roots from the heat in summer, the cold in winter and reduces the frequency of watering. Apply a loose mulch, over the planted area to a depth of 4 to 6 inches. Be sure to keep mulch several inches away from the trunk of the tree.
- Fertilizing: The most maples do not require any fertilizer for healthy growth. When trees are pushed with fertilizer it often invites disease and dieback in the stems. Once the maple has established a strong root system it will begin putting on top growth. This sometimes takes one to two years. Please be careful with fertilizers!
- Pruning: As in most of the trees a pruning done to an awareness is a method of care, otherwise it can be very harmful. In what follows we will see everything about the Japanese maple pruning.
3. What tools to use for Japanese maple trimming
There are several tools that need to be used to carry out the pruning of a Japanese maple. The choice will depend to a great extent on the type of pruning and the size of the fruit tree.
- Pruning shears.
- Ladder or scaffolding.
- Basic safety elements such as helmet and gloves.
Keep in mind that you must disinfect all cutting tools before pruning. This will help not to transmit diseases, you will have to do it before starting the pruning and every time you change plants.
4. When to prune japanese maple tree
There is not a single moment or time to perform the Japanese maple pruning. For example, winter, when trees are dormant, is best for some work, whereas late spring, after new growth has developed and while trees are filled with vitality, is best for other work. With good judgment, however, some pruning may be done at most times of the year.
Be sensitive and aware of what would be preferable for the tree at any particular time; it is best not to prune in early spring, when leaves and bark are tender, nor in the full heat of summer.
Japanese maples normally grow at a moderate rate and are well-behaved trees (unless in full sun). They do not need continual maintenance aside from two, possibly three seasonal pruning sessions a year.
5. How to prune or trim a Japanese maple
In general, it can be said that it is carried out in a way that is not complicated. If you follow the next tips you will not have problems to trim your Japanese maple:
5.1 Examine your Japanese maple before pruning
Start by examining and evaluating your tree from the bottom up and the inside out. Look at the bottom of the trunk and work your way up one branch at a time following it to its end.
Japanese maples often are multi trunked. Usually the skirt of the tree needs to be raised so that you can see the trunk(s). If you have a fairly new tree you may notice that some of the main branches are lanky and falling down. Some trees have instant character, while others take time to develop theirs.
There is a general rule to not remove more that 30% of a tree per year, so it may take more than one season to develop your perfect tree.
5.2 Remove the obvious
The elements you should always trim out on your Japanese maple are the following:
- Completely remove dead branches.
- Branches that are too vertical or too horizontal.
- Branches that criss-cross.
- Overlapping branches.
- Branches that are growing inward, or are too deformed.
- If two branches run parallel, remove one
You’ll often find deadwood at the bottom and inside of a tree, where branches have been shaded out. When removing a larger limb, the cut should be made just above the branch collar, which is the ridge or line where the branch joins an older branch or stem. Stand back and reevaluate the tree from all angles. Don’t prune your tree into a narrow hat rack with short branches.
5.3 Gently shape the remainder of the tree
Much of the twiggy growth on the main trunk and on the branches near the main trunk can be removed to expose and show off the branch structure, but leave the twiggy growth on the tips or gently thin it if it is too plentiful.
Avoid pruning a large branch back to a small side branch or you’ll get an unbalanced appearance. Periodically step back and examine your work from different angles. Look at your tree from the base up, following a branch upward to assess what and where to prune next. Don’t rush, and if in doubt, don’t cut.
5.4 Direct growth by controlling buds
Note that buds are arranged opposite each other on the stems and that they face the direction they will grow. When you cut back to the buds, two branches will form. You can direct the growth by choosing one bud and rubbing out the other.
5.5 Make your Japanese maple look good by pruning it
The trick to making Japanese maples look great is to separate the branches into overlapping layers that don’t touch each other. You want to be able to see between the leaf layers.
If lateral branches grow downward, crossing into the layer below, it should be removed or cut back to a side branch facing up and out. The same applies to lateral branches that grow upward into the above layer. This is how the tree becomes layered, like a series of fans. This last step is often fine-tuned in late spring or early summer when the trees are in full canopy.
6. Japanese maple pruning according to the time of year
So far we have seen some general tips for pruning the Japanese maple, but they can not be applied in the same way at any time of the year.
6.1 Pruning in winter
Winter is the time for structural pruning Japanese maples most, if not all, of the leaves will have dropped, leaving a gorgeous potentially gorgeous «winter silhouette.»
The tree is dormant, the bark is less tender, and large cuts heal more quickly during this season. This is when we can actually change the architecture or the lines of a tree in significant ways: to reveal more of its essence, to resolve a spatial problem (because the tree is too big), to enhance the surrounding environment (such as training around an entry way), or simply to make a more beautiful and healthy tree.
6.2 Spring Pruning
Spring is predominantly a time for shaping and thinning, particularly to create that lacy, leaves-dancing-in-the-wind look. New layers of bark are tender and rip easily, so it is important to be careful with cuts and saw work, and to avoid pruning off large branches, unless absolutely necessary for the health of the tree.
Focus on the finer pruning tasks: thinning crowded branches, shaping, and thinning out leaves (by hand or with scissors).
When finished, the tree will have fewer leaves, but the leaves will stand out more, and the tree will appear more delicate, fresher, and better shaped. You should be able to see light coming through the tree, which will enhance a sense of spaciousness and depth in the garden.
6.3 Summer pruning
Pruning your japanese maple may or may not be necessary during the warm days of summer. This depends, in part, on whether the tree receives a lot of direct sunlight.
Summer pruning is usually limited to removing aggressive water sprouts growing straight up through the tree. This is not the best time to do other types of pruning on Japanese maples.
7. Trimming an upright japanese maple tree
Pruning the upright Japanese maple can be summarized in four simple steps:
- First step: this consists of pruning the lower limbs that surround other low growth shrubs or, possibly, preventing a walkway.
- Second step: as a second measure we can use dead wood, that is, any dead twig or fragile branches that no longer produce foliage.
- Third step: is to separate the tree into layers. Remove branches that intrude into the layers above and below them. T
- Fourth step: as a last task you should uniformly thin the branches. Remove some small side branches and keep others to obtain a thinner overall appearance.
8. Summing up the pruning of the Japanese maple
In case you have doubts about how to prune a Japanese maple I make a simple summary with three tips:
- The pruning needs of Japanese maples consist of removing dead or damaged wood and any small crossed shoots in the fall and opening up the tree’s centre to allow for air circulation.
- Any pruning to shape should be done sparingly and in the late summer to early fall when the sap has slowed. This type of pruning should not be done in winter or early spring to prevent die back and/or infection of cut stems. Any major spring pruning can result in bleeding stems and possible infection.
- Shaping of your Japanese maple should be done slowly and from the inside to the outside. Stand back and study the tree’s shape carefully and try to visualize the form before making the cut and removing the branch. These efforts will reward themselves in the long run when you have a beautifully shaped tree.
8. How to prune the Japanese maple bonsai tree – Explanatory video
The bonsai is an art, where pruning is a key point. Since to correctly develop the pruning of a Japanese bonsai maple you would need a special post, I have chosen to select a video (From the Bonsai Boise channel) where you can consult on this subject.
So here we come with this article, I hope it has been clear how to prune a Japanese maple, and do not hesitate when you have to cut it.
Pruning Japanese Maples by Michelle Le Strange, UC Master Gardener.