Japanese maple: planting, care and pruning


There are many varieties of Japanese maples, of different sizes, but all without exception have more or less cut foliage, of great beauty, adorned with autumnal colors of the most beautiful effect, igniting the parks and gardens of their sublime tones. Depending on its height in adulthood, this tree can be planted in isolation, in groups, in rock gardens and even, for smaller varieties, in large vats. We cannot resist its charm, whether with variegated foliage, purple, gold or different greens. But be careful to offer it all the living conditions it needs to thrive and to choose the varieties best suited to the climate and the soil of its garden. Let’s do a check in.

Plant a Japanese maple

Japanese maple is a deciduous tree who particularly appreciates situations slightly shaded and it must be installed sheltered from prevailing winds in cold regions even if it is quite hardy (this means that it resists frost quite satisfactorily). However, only the young shoots are vulnerable in some regions where spring frosts are still rife because they can really damage them.

Although he does not like the full scorching sun or the scorching heat, he still needs a beautiful light because it is this which allows it to retain the magnificent color of its foliage. Note, however, that the purple varieties are the ones that need full light the most.

As to ground, he must be lightweight, moderately acidic and fresh (which keeps humidity), but the Japanese maple hates having its feet in water. So the ground must be well drained. Attention, this tree does not appreciate at all the calcareous earth to which it is even downright intolerant.

The different varieties of Japanese maples are marketed in clod. They can therefore be planted almost all year round (except in winter). However, the best period to install a Japanese maple in the ground is theautumn and the planting method is the following :

  • Dig a fairly generous planting hole that should be at least twice the size of the root ball.
  • Place a drainage layer of about twenty centimeters at the bottom of the hole (pebbles, pebbles, etc.),
  • Prepare an adequate mixture of 40% topsoil, 30% so-called heather soil and 30% very high quality planting soil or, better, compost. We insist that the Japanese maple must not be planted in limestone soil under any circumstances. On the other hand, it can be satisfied with a neutral ground as long as it is not heavy.
  • Sift the planting soil and add two large handfuls of powdered horn.
  • Put a first layer of this soil on the draining bed.
  • Soak the root ball in water without taking it out of the pot until it is perfectly soaked.
  • Take the root ball out of the pot and gently loosen the roots without hurting them.
  • Place the shrub in a root ball in the center of the hole.
  • Place a stake in order to direct the shrub during the first months if necessary and to maintain it in the event of strong winds.
  • Carefully fill the hole with suitable soil, taking care not to bury the collar, which must imperatively be flush with the natural surface of the soil.
  • Firmly pack the soil without mistreating the roots, and make a small watering basin.
  • Fill the bowl with a good layer of homemade compost or a mulch of hemp, dead leaves and / or bark.
  • Water copiously.

If we wish plant several Japanese maples, it is necessary to space them from each other 2.50 to 3.00 m for large varieties and 2.00 m for smaller ones.

The planting a Japanese maple in a container is identical to planting in the ground. We do not therefore forget the draining bed to be placed at the bottom of the pot before placing the sieved soil. Clay balls do the trick very well. Obviously, we choose a container with a pierced bottom, sufficiently deep and wide, at least 50 cm deep and in diameter. It is important to be vigilant in terms of watering because the soil dries very quickly in pots.

Caring for a Japanese maple

As with any shrub, this one needsregular waterings during the first years after its planting, and more frequent in summer while it is still frail as well as during the few weeks which follow its installation in the garden or in pot because this favors its rooting. Be careful, however, not to let its roots bathe and not to water on frost days.

The condition of the connections which keep it to the tutor and replace them with larger ones as the trunk thickens. After some time, it is quite possible to remove the tutor, which becomes totally useless.

A mulching is strongly recommended because it slows down the evaporation of water. The soil thus remains very cool to meet the needs of the Japanese maple. Putting a mulch at the foot is also very useful to protect the roots of the tree against strong frosts, knowing however that the different varieties readily support -10 to -14 ° C if they are not too exposed to the icy wind.

From March to November, we take care to aerate the surface of the soil all around the foot of the tree thanks to hoeing allowing in parallel to weed. About the japan maple size, it is not absolutely necessary. In the spring, we are content at most to eliminate the dead wood.

A fertilizer for shrub should be done twice a year if planted pot, and it is useful to renew a part of the earth because it is quickly depleted under such conditions. It can possibly be placed in the shelter under a porch if the winter promises to be particularly harsh. A wintering veil can be wrapped around the box after planting. But this last point is not mandatory because in most climates, Japanese maple is able to spend all winters in pots without being protected down to -10 ° C. After a few years, the maple grown in containers should be repotted in a larger container.

Pests and diseases of Japanese maple

In poor growing conditions, this tree is sometimes the target of pests and diseases, namely:

  • Aphids, which is eliminated with black soap sprays diluted in lukewarm water.
  • Mealy mealybugs which must be dislodged by numerous sprays of a mixture of one liter of water, a teaspoon of 90 ° alcohol, black soap and vegetable oil.
  • Defoliating moths which can be removed either with infusions of wormwood, or with decoctions of tansy or pyrethrum in regular sprays.
  • Leaf burns, favored by climatic conditions unsuitable for Japanese maple. This is why it is essential to choose a place particularly well suited to this tree before planting in the ground. Leaf burns follow exposure to scorching sun and high dry winds or even salty winds in coastal areas. These are as many environmental stresses that harm this type of tree. A young plant can be moved just like a potted maple, but there is not much that can be done on a Japanese maple that has been planted for several years and the leaves drop early.
  • Black spot disease, which requires prompt treatment. You can use a nettle manure, a horsetail decoction or buy a copper fungicide.
  • Armillaria or root rot, a serious fungal disease that attacks the root system and eventually kills the tree. We eliminate the affected parts that we burn and we remove the soil to a depth of about fifty centimeters because the fungus in question spreads easily. The hole thus formed must be left as it is for a good year and we avoid planting in this place thereafter for at least 4 years.
  • Verticillium wilt, a fungal disease due to the presence of the fungus Verticillum which little by little deprives the tree of sap until its death by drying out. To avoid this disease, do not plant a Japanese maple in calcareous soil and, if it is grown in a pot, care must be taken to ensure that this container is fully pierced. But whatever the conditions, it is important not to let its roots bathe in water. Be careful with excessive watering. The only solution to adopt in the event of verticillium wilt is to cut the affected parts, even if it means unbalancing the silhouette of the tree.

Apart from the verticillium wilt that is quite common in these specimens, the Japanese maple is a tree that does not pose a problem. We can also see that it does not require special care. It is not very sensitive to diseases and parasites when it benefits fromexcellent conditions and is planted in the right place. So do not hesitate to indulge yourself by choosing various varieties to enhance your outdoor space.

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