Many Japanese maples are perfectly happy to be in full sun all day, particularly the varieties with red leaves, but generally, the majority will do best with sun in the morning/early afternoon and some shading or full shade in the hottest parts of the afternoon and early evening. This will vary depending on your location and climate.
Japanese maples grow best in Canadian Hardiness Zones 6-9, but like any tree, it takes a year or two to be established in the landscape. At the lower cold extreme zones, some additional protection measures may be necessary, depending on the variety of tree. And in fact, some folks grow these trees in places where the trees are kept in containers and brought into sheltered area over the harsh winter period. Totally possible.
As for summer, in the hottest locations in Canada, trees should be situated where they will receive less direct afternoon sun and kept away from very hot, light coloured south or west-facing walls. Having an understanding of the climate you live in and the hardiness zone will go a long way towards the long term health of your tree.
Established trees are fairly drought tolerant, need little to no fertilizer, and pruning typically is minimal. Many Japanese maples can be pruned to sizes more appropriate to your requirements. If fertilizing is to be done, it should be applied early in spring only. Organic fertilizers are always best. The nitrogen-phosphorous-potassium (NPK) ratios are lower with organic fertilizers, typically 4-4-4 or 5-3-4. Adding fertilizer is more significant for container trees than trees in the ground.
Finally, drainage matters. Japanese maples grow in a variety of soil types. For containers, use the right potting mixtures, such as a mixture of fresh and composted barks, with some perlite, if your tree is in a container. If planted in the landscape, mounding up the soil where you intend to plant the tree above the surrounding garden bed will assist with drainage. Adding some of that composted bark is also beneficial. Heavy clay soils are challenging, but if that's what you have you could add small rocks into the hole and bark mulch mix to help aerate the area somewhat and give the tree a good chance to avoid drowning during the wet times. This is also where ensuring the rootball is slightly planted above the overall soil grade is even more critical. When it comes to watering, trees in pots will need more frequent watering than trees planted in the landscape. And smaller pots dry out faster than larger ones. During drought or unusually hot periods, trees need extra water. Again, containers will require more than trees in the landscape.
A little bit of effort to educate yourself about Japanese maples will help you establish your tree, and make for a happy and healthy tree. And a happy owner! Use the link below to find your hardiness zone.
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