The Japanese Maple ( Arce palmatum ) is a small tree native to Japan and South Korea. Its distribution is increasingly expanding, and it is now cultivated in various countries in temperate regions around the world. This tree has been cultivated using the bonsai technique for centuries. I invite you to learn about its characteristics and care to understand what makes it such a sought-after tree.
The Japanese Maple
This Asian tree, colloquially known as "Japanese Maple," "oiroha kaede" (in Japanese), or "Phyllomorphic Maple," is scientifically identified by botanists as Arce palmatum and belongs to the Sapindaceae family (formerly Aceraceae). It is a small, deciduous tree, reaching approximately 10 meters in height, that thrives in shady locations.
From an etymological perspective, the Latin word * Arce* means "sharp" or "pointed," a reference to the morphological characteristics of its leaves. This is also because, according to ancient Chinese folklore, its trunk was used to make spears. Its admirers eagerly await autumn to harvest its samaras (winged seeds), which rival its beautiful flowers.
The genus Acer has around 100 species, most of which are distributed in East Asia, between Japan and China, and the rest between the United States and temperate countries of Europe. Among the other described species of the genus Acer are Arce campestre , Arce glabrum, Arce japonicum, Arce griseum, Arce oblogum, Arce circinatum, and Arce negundo , among others.
Features
The Japanese maple ( Arce palmatum ) is a tree that grows to between 6 and 10 meters tall, with some specimens reaching up to 16 meters. Its palmate leaves measure 4 by 10 centimeters in width and length, with nine lobes ending in points. During autumn, its leaves turn red or purple in the days leading up to their fall. It is a temperate climate tree, tolerating maximum temperatures of 30°C and minimum temperatures as low as -18°C.
It is a small tree that has several branches close to the ground, while it is growing, during its juvenile stage it has a pyramid shape and already in its adult stage it acquires a dome or dome shape. It behaves as an accessory plant that grows in the undergrowth. The attraction of this tree is its colorful reddish-purple leaves, transparent in spring, which become faint in summer and become a brilliant purplish-red in the autumn season.
Its inflorescence is top type, this means that the terminal flower of the floral axis is the first to open, while the other flowers grow laterally. Its flowers are whitish pentapetals. Its flowers that grow in its summit-type inflorescence, have 5 red-purple sepals, 5 whitish petals, with winged, dry, indehiscent disamara capsular fruits, each 2 to 3 centimeters long, its seeds 6 to 8 millimeters.
The flower buds begin to sprout in the spring season, this allows their winged or disamara capsule-type fruits to begin to disperse by the fall season. Time when its growers go to collect Japanese Maple seeds to reproduce it. To propagate Japanese Maple, they have to stratify their seeds.
recognized subspecies
In nature, this species exhibits many genetic differences; a single parent plant can display diverse traits in size, leaf shape, and color. It has developed several cultivars, of which only three subspecies are recognized, all derived from the species Arce palmatum. These subspecies are distributed across the Asian continent and exhibit slight morphological differences that lead to their classification as subspecies.
- Maple palmatum subsp. Matsumurae: this subspecies has the largest leaves, measuring 9 to 12 cm wide, with 5 or 9 lobes with doubly serrated margins. It grows in Japan, at high altitudes.
- Maple palmatum subsp. Palmatum: the leaves of this subspecies are smaller, 4 to 7 cm wide, with 5 to 7 lobes and doubly serrate margins. The length of the wings of its seeds is 10-15 millimeters. It lives at lower altitudes, in central and southern Japan except for Hpkkaido.
- Acer palmatum subsp. amoenum: it has leaves 6 to 10 cm wide, with 7 to 9 lobes and simple serrated margins. Its seeds have wings between 20 to 25 centimeters. It lives in the higher altitude regions of Japan and South Korea.
Cultivation of this tree
This tree adapts well in all the temperate countries of the planet where it is grown. Japan, one of its countries of origin, has been cultivated for centuries. It is a plant that was taken to other countries from the XNUMXth century, since then there are many commercialized and related cultivars in the gardening of the European continent and North America. Red-leaved Japanese Maples are the most widely grown, as well as trimmed green-leaved ones. It is widely used for making bonsai.
its cultivars
Japanese Maple cultivars are not all grown in the Western Hemisphere and some have even been lost. The demand for this tree by horticulturists results in the production of new cultivars every decade. These are selected for phenotypic factors such as leaf shape and size, either deeper or shallower lobes, as well as palming. Coloration of the leaves, texture and color of the bark and size.
As a result of their crosses, some cultivars are larger and more vigorous trees than the species itself. Most are shrubs that do not exceed 5 meters in height. Other cultivars more sensitive to certain environmental conditions are only 3 meters tall and are grown in pots. Some malformed or dwarfed cultivars can grow from mutated plants, witches' brooms, or artificially selected after many generations.
To date, there are 1000 cultivars of the Japanese Maple, which, being hybrids, only reproduce asexually by grafting, a reproduction technique that allows for fast-growing trees with certain characteristics. The selection of cultivars by experts is conditioned by some morphological characteristic such as: the color of their leaves, their size, the size they reach, among others.
The benefits of reproducing plants by grafting with respect to plants by seeds, is that the grafted Japanese Maple whoever acquires it will have a 5-meter tree. These cultivars originated from crossbred plants, possibly having been selected for many generations. Most of them present their own characteristics in the different seasons; be these: variations in the color of the leaves, trunk bark brighter or less bright. This can be a problem, since a cultivar can have many names.
Some examples of cultivars
Because there are so many cultivars, it is difficult to list the main cultivars of Japanese maple. Below are the cultivars that are easier to find in nurseries. These plants can be an excellent selection to grow directly in the garden and to grow in pots.
- Aka shigitatsu sawa: plant with white pink leaves with green veins
- Low Ao: A dwarf shrub with bronze-green summer foliage
- Atropurpureum: is, one of the best known. It has deep red leaves throughout the year.
- Bloodgood: is an improved cultivar of Atropurpureum. It is more resistant to warmer temperatures.
- Butterfly: Its leaves have white edges.
- Deshojo: The leaves of this cultivar are soft and bright red.
- Dissectum: Its leaves are shaped like needles.
- Golden Pond: Plant with yellowish-green summer foliage
- Goshiki koto hime: Delicate variety, with dwarf variegated leaves
- Higasa yama: Plant with wrinkled leaves, variegated with yellow
- Hupp's Dwarf: Small, dense shrub with miniature leaves
- Issai nishiki kawazu: very rough stem, stiff bark
- Kagiri nishiki: similar to 'Butterfly' but more shades of pink
- Karasu gawa: Slow-growing tree, variegated with bright pink and white
- Katsura: Yellow and green leaves, dotted with orange.
- Koto no ito: light green leaves, thread-like leaves
- Little Princess: Small tree (does not exceed 2m), with an irregular size.
- Mama: Dwarf bushy plant with extremely variable foliage
- Masu murasaki: – a small tree with purple leaves
- Mizu kuguri: new growth with orange spots, very wide habit
- Nishiki gawa: small pine-like tree, desirable for bonsai
- Nomura nishiki: purple black, pointed leaves
- Osakazuki: This cultivar is a small tree that turns a spectacular shade of red in the fall.
- Peaches and Cream: Tree similar to 'Aka shigitatsu sawa'
- Pink Filigree: finely dissected cultivars, pink brown leaves
- Red Filigree Lace: Cultivar delicate, finely dissected, purple-black
- Sango Kaku: It is a beautiful tree with red or pink leaves in autumn.
- Seiryu: They are trees with finely dissected leaves, orange-reddish in color in autumn.
- Shikage ori nishiki: cup-shaped shrub with purple foliage
- Skeeter's Broom: derivative of 'Bloodgood' "witch's trash"
- Tamukeyama: Cultivar finely dissected, purple black, waterfall habit
- Tropenburg: slender tree, upright growth, convex lobed, purple leaves
- Tsuma gaki: Cultivar with yellow leaves edged with purplish red.
- Uki gumo: prominent, white variegated
- Waka momiji: another "coral bark maple"
- Yuba e': upright tree with scarlet variegated
red foliage tree, atropurpureum y blood good
In addition to the cultivars listed above, various groups of cultivars have been chosen over time and their planting enacted. They become difficult to distinguish, since many of them offer them with the same names as cultivars, or even being propagated by grafting. Specifically, various blackish-red Japanese maples are offered under the names "Atropurpureum" and "Bloodgood." Also, many maple cultivars that have delicate ribbon foliage are sold under names such as "Dissectum," "Filigree," "Laceleaf"
Other species of the genus Arce
The common name “Japanese maple” is also used as a generic name for other tree species of the genus Maple , due to the phenotypic similarity of these individuals and their origin in Japan, Korea, and China. These are:
- maple duplicatoserratum (no. a. palmatum var. pubescens Li)
- japonicum maple Thunb.- dwarf Japanese maple
- maple pseudosieboldianum – korean maple
- shirasawanum maple Koidz.- full moon maple
- sieboldianum maple Mic.- Siebold Maple
These are species of the same genus , Arce, that have morphological and genotypic differences; however, this has not prevented horticulturists from crossbreeding them, resulting in interspecific hybrids. Likewise, in nurseries, individuals of the species Arce palmatum are used as mother plants for other species.
Taxonomic Classification
The species Arce palmatum was described by Carl Peter Thunberg and published in 1784 in Systemat Vegetabilium . Editio decima quarta 911. 1784.
Etymology of his name
Etymology is the science that studies the origin of words, this case of the words that describe the plant and were used for the scientific name of this tree.
The genus name "Arce" comes from the Latin word *acer*, meaning "sharp" or "pointed." It was applied to this plant to refer to the points of its leaves or the hardness of its wood, which was apparently used in ancient times to make spears. According to Pliny the Elder, in the 16th/17th century, when referring to other species of this genus, the species of this plant is specified with the Latin word * palmatum*, meaning "palm-like," a reference to the shape of its leaves.
Accepted Varieties
- maple palmatum subsp. amoenum (Carrière) H. Hara
- maple palmatum f. latilobatum (Koidz.) Ohwi
- maple palmatum subsp. matsumurae Koidz.
Synonymy
- amoenum maple Careers
- decomposed maple dippel
- dissectum maple Thanb.
- formosum maple Careers
- maple friederici-guillelmii Carr
- incisor maple dippel
- jucundum maple Careers
- ornate maple Careers
- pinnatifidum maple dippel
- maple polymorphum Siebold & Zucc.
- powdered maple dippel
- maple ribesifolium dippel
- maple roseomarginatum (VanHoutte) Koidz.
- blood maple Careers
- blood maple var. amoenum (Carriere) Koidz
- Septemlobum Maple Thanb.
- sessilifolium maple Siebold & Zucc
- sessilifolium negundo My Q
Management of your crop
The Japanese maple tree ( Arce palmatum ) thrives in deep, well-drained soils. Because it grows in the understory of forests, the larger trees protect it from direct sunlight. Therefore, it should be cultivated in sheltered locations where it receives indirect sunlight to avoid damaging its leaves.
It is a plant that demands frequent watering, without flooding the soil and environmental humidity, so water must be sprayed on its foliage. In the winter season it must be protected from frost at temperatures of -10°C. To remove dead branches and keep their shape balanced, it is suggested to prune eventually
Pot Maintenance
The maintenance of the Japanese Maple in pot, has to provide the plant with the resources of nature, according to its requirements so that it develops and grows well. If it is grown in a pot, the culture medium or substrate must have good drainage, with an acid pH, between 4 and 6. Expanded clay can be placed on it, which helps to acidify the soil and aerate for the good growth of its roots and absorbs well. the ground water.
Frequent watering is suggested, since it is a plant that naturally grows in humid forests of temperate regions. The irrigation water must also be acidic, for this it is suggested to acidify the water in the following way: add the juice of half a lemon in a liter of water. You can also irrigate with rainwater 3 or 4 times a week, and even more in the summer season.
Plant the Japanese maple tree, in a location where this tree will get shade and indirect sunlight. Some cultivars such as Seiryu and Osakazuki, resist a few hours of direct light, it is suggested to place your specimen in a lighted and ventilated place, but indoors so that the sun's rays do not directly reach the leaves, as it can burn them.
When grown in a pot, it is recommended to repot this Japanese maple ( Acer palmatum ) every two years in spring, before flowering. If spring passes without repotting, it can be done in autumn, after the leaves have fallen. Repotting should be done once the tree is mature, at least 36 months old.
These potted trees need to be repotted when they are two years old and then every other year, and especially if the soil is very porous or they are in a place with a good climate for maples, he suggests doing it to a pot 4 centimeters larger. where it was grown from.
Care in external spaces
It is recommended to plant it in places with acidic soils, that is, with a pH between 4 to 6. In case of limestone soil, pine leaves or iron sulfate must be added, to help acidify (lower the pH values) and achieve the pH 4 to 6 in the land where it was planted.
Watering has to be frequent, preferably between 2 to 3 times a week and even 4 times a week in the summer season.
When it is planted in a garden it has to be placed under the tallest trees in the garden as this type of tree grows in nature. It can also be near a high wall to protect it from the sun's rays.
To transplant it to the garden, it is suggested to do it in the spring season, while the new leaves do not sprout. When you are going to transplant it, choose the garden spot that has shade and enough space for the growth of your Japanese maple. A hole about 60 centimeters in diameter and 60 centimeters deep is opened. Place the tree that already has to be over 2 years old, fill it with fertilized black earth that has an acidic pH, as well as the earth that you took out of the hole or hole.
Phytosanitary treatment
Pruning is used to control the growth of tree branches, remove damaged or diseased branches. There are some cultivars that grow quite tall and even taller than expected or wanted, it is good to prune it to keep it compact. If you have a Japanese Maple bonsai, you need to learn how to prune it to the requirements of a miniature adult tree.
Japanese-made trees are suggested to prune in the autumn or winter season, when the tree is in the vegetative stage, when pruning it is suggested to cut the intersecting branches; those that grew very long; to act as a guide, which will be cut to take the tree to remove low branches; and those weak or diseased branches.
apply nutrients
These trees have to be fertilized with fertilizer for acid soils according to the product's recommendations, it is applied 50 centimeters from the plant around depending on the crown of the tree, with the aim that it does not burn. The frequency of fertilization depends on the requirements of the plant, the conditions of the soil (perform a chemical analysis of the soil) and the time of year. When you fertilize the soil it has to be moist.
Control of pests and diseases
It is a fairly resilient tree, which makes it resistant to diseases and pests. However, it is susceptible to pests such as mealybugs, spider mites, and aphids when the environment is very dry. As for diseases, it could be affected by fungi of the genus Phytophthora.
How to control the attack of any of these pests or fungi?
Although it requires frequent watering, the soil does not have to be waterlogged. To control this, a wooden stick is inserted into the pot or into the ground to keep track of soil moisture. If the substrate or soil is dry, the stick will come out almost clean, this indicates that the soil is dry. If so, it has to be watered, without flooding the soil.
Provide humidity to the environment. To increase the humidity of the environment, it is suggested to place several glasses of water around the plant. Spraying is not suggested to prevent the water that falls on its leaves from being burned by the sun's rays in case of high solar radiation and from there a possible fungal attack.
Preventive treatments with biological insecticides, such as nettle purin or Neem oil, which can be purchased at garden stores, are suggested. Homemade insecticides can also be prepared at home as an infusion with garlic cloves, strain it and spray the plant first thing in the morning.
Reproduction and Propagation
The Japanese maple ( Acer palmatum) can be propagated through both asexual and sexual reproduction. Sexual reproduction is carried out by scarifying the fruit to collect the seeds. One method involves soaking the seeds in hot water (43°C) for two days or 48 hours. After this time, the seeds are removed and sown directly in the soil. It is recommended to water them after three days to avoid damaging the roots. Sexual reproduction does not guarantee identical plants, but rather individual plants that are different from one another.
If you want to preserve the phenotype and genotype of a particular Acer palmatum individual , it must be reproduced asexually, since the resulting individuals are clones of the parent plant.
Reproduction by seeds
Japanese maple ( Acer palmatum) seeds are collected in the fall and placed in the refrigerator for three months at a temperature between 6-7°C. This is because, in order to germinate, the seeds need time at low temperatures, similar to their natural environment. Once collected, they are packaged in a clear plastic container with vermiculite, covering them with a thin layer. The container is slightly moistened, and a small amount of sulfur or copper is added as a fungicide to prevent fungal growth.
As you have to store for three months, it is suggested to remove the container from the refrigerator and open it once a week so that the air is renewed. After three months they can be planted in a pot. The planting substrate or soil must have an acidic pH (between 4 to 6) and if all goes well they will germinate in about two months.
Reproduction by cuttings
This method of reproduction is one of the fastest and most effective. Japanese maple cuttings or cuttings, a juvenile branch with a diameter between 2 to 4 centimeters and a length between 40 to 50 centimeters is cut, the pruning of the branches to prepare the cuttings or cuttings has to be done in spring. To make them root faster, it is suggested to impregnate water with hormones to root. Then the stakes are placed in the pot with a porous soil or substrate, and that you are a little moist. In a period of 5 to 6 months it will begin to emit roots.
Playback by layering
Another method of reproduction is air layering. To make air layering, cut the bark about 10 centimeters wide, place a bag, moisten it with water and impregnate it with rooting hormones. Then you put a bag on it, which you tie to one end of the branch, fill it with suitable substrate for plants that grow in acid soils, moisten it and then tie it to the other end.
The substrate must be kept moist, this can be done with an injector 3 to 4 times a week. In a period between 5 to 6 months the roots will come out.
Reproduction by graft
The grafts are carried out by professionals in horticulture. It is done as follows: The mother plant, pattern plant or rootstock is chosen. This is a plant to which the branch of another Japanese maple will be placed, a deep cut is made to its stem during the spring season
Then, a semi-woody branch (this will be the graft) is cut and inserted into the rootstock, mother plant or pattern plant.
To finish, it is joined well with an adhesive tape to make grafts. If the graft was done well, between 2 to 4 months after the graft, its leaves will sprout. While pruning the leaves of the mother plant or rootstock, so that the nutrients can be used by the graft.
Use of Japanese Maple
In temperate countries it is possible to see adult specimens of Japanese Maple, with a height of 50 centimeters, as it is the most used species in the art of Bonsai. Many are the Japanese Maple trees, which adorn homes and other interior spaces. The Bonsai technique is a gardening practice that originated in Chinese Taoist temples, the horticulturists who practice it consider that through its practice heaven and earth can be linked, evoking eternity.
This horticultural practice was introduced 800 years ago in Japan. The syllable "bon" refers to a tray, and "sái" refers to nature. Being a slow-growing tree makes it a favorable plant, to apply the bonsai technique.
The Japanese maple (Acer palmatum ) is an ornamental plant, grown in gardens (protected from the sun), in pots as a houseplant, or as a bonsai, ever since it began to be exported from Japan in the 19th century. It has naturalized in temperate climates in Asia, Europe, America, and other parts of temperate regions.
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