These Japanese Maples have been planted over a 30 year period. My garden is Zone 5 at 2100 ft or 610m in the West Kootenays of BC. We get winter!
The oldest Maple is the Langley Maple which I got at a nursery in Langley BC. We live about 600 km east of Vancouver and 600 Km West of Calgary pretty close to US border, north of Spokane WA. We get a lot of snow so I have to brush snow off of some of the weeping type maples in the winter.
I have collected seeds and small seedlings from various local ares and friends. I have a few of them in pots, not bonsai.
I love my Japanese Maples.