What plant hardiness zone is Rainy River

Rainy River is located at Rainy River District, Ontario (ON), Canada.

Plant hardiness zone (winter frost zone or gardening zone) for Rainy River is 4a by the PHZ Canadian scale.

Plants of 4a PHZ hardiness zone suitable for outdoor gardening and growing in this winter frost zone 4a PHZ.

Also perennial plants from the equivalent USDA zone 3a with coldest winter temperature −40 … −37.2 °C and lower can be grown here, see list of plants for 3a USDA winter zone.

Rainy River, Ontario @ wikipedia.