What plant hardiness zone is Santa Rosa
Santa Rosa is located at Sonoma County, California (CA), USA.
Plant hardiness zone (winter frost zone or gardening zone) for Santa Rosa is 9b by the USDA scale.
Coldest zone's winter temperature is +25 … +30 °F.
Plants of 9b USDA hardiness zone suitable for outdoor gardening and growing in this winter frost zone 9b USDA.
Santa Rosa, California @ wikipedia.