Japanese Maples
Maple Leaf A.j.f. Aconitifolium (fall), A.p. Katsura, A.p.d. Inaba shidare, A.p. Orido nishiki


CARE OF JAPANESE MAPLES

Summer heat and draught problems:
Mulch your trees with 2 1/2 - 3" of shredded bark, preferably hardwood, to insulate the roots and prevent water from evaporating around the tree.

Water deeply twice a week; water more often if it is a newly planted tree or a container-grown tree.

Leaf tip burn is unsightly, but not a cause for panic. It is most often a result of too much water, too little water, an underdeveloped root system (as a newly planted tree would have), or too much fertilizer, especially if a salt based fertilizer is being used. Afternoon shade and good watering practices help, but in some conditions you may have to live with it for the rest of the season. Under extremely stressful conditions your maple may drop all its leaves. Do not despair. Maples have a secondary set of leaves waiting for just such a time. The tree is protecting itself and telling you it is not getting enough water.

When your tree is feeling stressed do not try to fertilize it into feeling better. Do not fertilize it at all. Fertilizer is a stimulant and your sick tree does not need a stimulant. Instead, feed it kelp meal or something similarly rich in trace elements. Also, if your tree is stressed, be on the lookout for other problems such as insects or disease to which it will be more susceptible at this time. Catch these problems early so you can deal with them immediately and prevent a spiral of decline.

Fall is a time of great opportunities:
Pruning for form is best done in late summer or early fall. Good form is largely a question of personal taste. We like to let air and light into the center of the tree so that we can see the tracings of branch structure. Working up from the base and from inside to out, clean out small twigs growing along the trunk and major branches, dead wood, and crossed and rubbing branches. Stand back and look carefully at your tree's shape. If it is not pleasing, look for what you need to remove to improve its form. Before making each cut, study where the branch goes and visualize the tree without it. Cut just above a live bud or just in front of the collar (the small ridge where a branch attaches to another).

Planting in the fall can be very rewarding. Try to plant at least 4 to 6 weeks before the ground freezes. The roots get a chance to establish themselves, and, come spring, the tree will be ready to put on new growth. If there is no rain be sure to water until the ground freezes and in the early spring.

Mulching is always a good idea for fall; it will help insulate the roots for winter and protect their early spring growth.

Winter care of your Japanese Maples:
Make sure your trees are well watered in the late fall and up till the time when the ground freezes. Mulch with about 3" of shredded hard bark, keeping it a few inches away from the trunk to allow air to circulate.

After severe winters many people find branches snapped out of their dissectums. To help prevent this, try not to let branch tips freeze to the ground; when they do they lose the capacity to move and give and the burden of heavy snow on the top center can cause branches to crack or even break. It is a good idea to remove snow accumulation from the treetops as soon as possible. At the same time, be cautious of a coat of ice while you are removing the snow. Do not try to remove the ice as well. If there is ice on the branches, the branches themselves are frozen. Tampering with them at this point can result in whole branches breaking, the tips snapping off and the bark being badly damaged. To minimize the burden of winter hazards, remove dead leaves that cling to the ends of branches before snow or ice come and do not plant where snow or ice will slide off a rooftop and land on the crown of the tree.

Spring attention:
Japanese Maples are extremely vulnerable in spring. They leaf out of winter dormancy with the first warm weather. 'Katsura' and 'Ueno yama' are among the first. Tender new growth is then at the mercy of a late spring frost. If your tree is young and small enough, protect it from these frosts by covering it. It is the frost more than the cold that is the danger; a good wind can save the day.

Damp, hot springs can be equally dangerous due to the fungal problems they bring such as Botrytis, Pseudomonas and Fusarium. Good air circulation, soil drainage and sanitation practices all help prevent these problems.