Japanese maples are easy to grow. They have a few basic requirements. Ample watering (they come from monsoon rainfall areas) and well drained soil are the minimum essentials. Protection from hot drying constant winds will keep foliage attractive. A special thing to do for containerized plants is to move them into full sun as they leaf out. If you do this, the leaves will become acclimated to full exposure and be tougher. They can then take any degree of shade and can also remain in full sun. (Some tender varieties are sun sensitive and will need a bit more protection always, but the majority will favor this kind of treatment). Let the leaves mature in full sun. Then you can relocate them after that leaf growth has hardened. Maples grown in shade will burn if moved into sun. Their leaves are not accustomed to strong light levels since they leafed out in shadier conditions.
Wait to do any pruning (unless is it obviously dead wood) until summer when sap flow has slowed. You can actually prune any time, but there will be excess bleeding if done while in active growth.
Feeding can be done in summer when there is active top and root growth. Any fertilizer will be taken up by the plant and utitilzed to the fullest degree if applied then. (if you apply fertilizer in winter or very early spring, you run the risk of burning the roots.)
Leaf color will be enhanced if moved into sunnier exposures when leafing out.
Japanese maples can grow in almost any soil type, but well draining soil is a must for healthy growth. Heavy soils can be improved with large amounts of humus or fir bark compost.
Many people ask about pruning off that long growth that happens on young or vigorously growing trees. I ask them, how big do you want your tree to grow? If they want the maximum size dimensions, I ask them why they would want to prune anything off. That is the growth that will turn into bushy branching as it matures in the following years and cutting off that ‘leggy’ growth will make your tree smaller in size.
If left to follow their own direction, the various varieties show an amazingly differenty growth pattern, unique to each variety. So let them grow to develop their own personalities. You can remove obviously poor branching (crossing branches, bad crotches, etc. while young in growth and then the tree will grow more branches in the areas which you will like better.
Typical species in the ‘Japanese maple group are Acer japonicum, A. palmatum, A. sieboldianum, A. shirasawanum. There are many other species of maples that come from Japan and the orient as well as around the world. The maples are a very large group!