Zone 8 runs in a curve all across the United States reaching from Washington, down to Arizona, then curving around to North Carolina. While these areas do have frost, they have milder weather that leads to healthy growing seasons. Portland, Salem, Ridgecrest, Austin, Dallas, Seattle and Tallahassee are just a few of the cities that enjoy this mild weather.
Zone 8 has two subzones, Zone 8a and Zone 8b. These Zones are differentiated by their minimum average winter temperature of 10 degrees F to 20 degrees F. Respectively, Zone 8a is 10 degrees F to 15 degrees F, while Zone 8b is 15 degrees F to 20 degrees F. This Zone is the most common warm Zone in the US! Using tricks like mulch can help you extend your long growing season even a bit further, but you will have to consider both the hot summer months and the frost season.