Answer: Location is the most important factor in planting Japanese maples. No matter which variety you select, you must plant them in the understory of larger shade trees, preferably out of the way of the extremely drying winds of winter. [In winter when the ground is frozen, there is no way for trees to compensate for the loss of water caused by wind action. The stress of this deprivation is often fatal to Japanese Maples.] The ideal site is under a larger tree located on the east side of a wind-blocking structure (a house, garage, or thickly-planted windbreak) so long as the tree receives about 1/2 day of sun. In fact, by planting under larger trees, you will be assuring yourself of beautiful fall colors since the trees will be protected from hard frosts.
Like many other plants, Japanese maples like loose, well-drained soil with ample organic matter. Don't expect much top growth in the first season after planting as your tree is putting its energies into root formation. A good mulch is essential, of course.
Now that your tree is in the ground, water it deeply once or twice a week to encourage good root establishment.
Best wishes with your tree.
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