Growing Info

Many Japanese maples are perfectly happy to be in full sun all day, particularly the varieties with red leaves. 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. Growing Japanese maples in zones below 6 are a gamble. Some will survive, some will not. At the lower cold extreme zones, some additional protection measures may be necessary. Some of our customers grow these trees in places where the trees are kept in containers and brought into sheltered area over the harsh winter period. 

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 (in the landscape) 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 and should be of the slow-release variety. 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 because these container trees are depending on you for their growing needs. 

Drainage matters! Japanese maples grow in a variety of soil types but too much water will kill them! For containers, use the right potting mixtures, such as a mixture of fresh and composted barks, with some perlite. If you cannot find bark mulches, mixtures made for acid-lovers (coniferous, azaleas/roses/rhodos) is a substitute. 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. Mulch 2-4" to retain some moisture and protect the rootball from the sun/wind.

Use the links below to find your hardiness zone. First links are from Plantmaps and the second one is from the Government of Canada. Plantmaps show zones as being warmer than Govt listed zones and we tend to favour those based upon customer feedback and warming climatic conditions of the years.

Plantmaps:

BC  AB  SK  MB  ON  QC  NB  NS  PE  NL 

Govt of Canada:

http://planthardiness.gc.ca/?lang=en&m=24&s=p&speciesid=1000000&phz=phz1981-2010&bc=1