What plant hardiness zone is St Thomas

St Thomas is located at Elgin County, Ontario (ON), Canada.

Plant hardiness zone (winter frost zone or gardening zone) for St Thomas 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.

St Thomas, Ontario @ wikipedia.