What plant hardiness zone is Black Diamond

Black Diamond is located at King County, Washington (WA), USA.

Plant hardiness zone (winter frost zone or gardening zone) for Black Diamond is 8b by the USDA scale.

Coldest zone's winter temperature is +15 … +20 °F.

Plants of 8b USDA hardiness zone suitable for outdoor gardening and growing in this winter frost zone 8b USDA.

Black Diamond, Washington @ wikipedia.