What plant hardiness zone is Alta Sierra

Alta Sierra is located at Nevada County, California (CA), USA.

Plant hardiness zone (winter frost zone or gardening zone) for Alta Sierra is 9a by the USDA scale.

Coldest zone's winter temperature is +20 … +25 °F.

Plants of 9a USDA hardiness zone suitable for outdoor gardening and growing in this winter frost zone 9a USDA.

Alta Sierra, California @ wikipedia.