What plant hardiness zone is Blue Mountains

Blue Mountains is located at Grey County, Ontario (ON), Canada.

Plant hardiness zone (winter frost zone or gardening zone) for Blue Mountains is 6a by the PHZ Canadian scale.

Plants of 6a PHZ hardiness zone suitable for outdoor gardening and growing in this winter frost zone 6a PHZ.

Also perennial plants from the equivalent USDA zone 5a with coldest winter temperature −28.9 … −26.1 °C and lower can be grown here, see list of plants for 5a USDA winter zone.

Blue Mountains, Ontario @ wikipedia.