What plant hardiness zone is Rock Island

Rock Island is located at Colorado County, Texas (TX), USA.

Plant hardiness zone (winter frost zone or gardening zone) for Rock Island 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.