Zone 8 Planting Calendar. Decked out with toppings, it can stand on its own. Here is some general info for USDA zone 8a to help you get started. Planting Zone 8. The high-temperatures of Zones 8 … Extending up the western coast, Zone 8 features average minimum winter temperatures of 10 to 20 degrees F. With hot summers and mild winters, growers typically enjoy a long planting … Average Date of Last Frost (spring) March 15: Average Date of First Frost (fall) November 15: Lowest Expected Low: … You’ll have to fine-tune your own seed starting schedule for zone 8, since frost dates vary within the zone. Now it’s time to figure out when to start seeds in zone 8. Some will specify a planting … Planting in Zone 8a. The lists are based on planting season (winter, spring, summer, fall) … If you live in or around the Charleston, SC area (Zone 8), here is a handy planting calendar for your garden. Zone 8 is considered one of the warmest plant hardiness zones for a large portion of the southern United States. Delicious baked, fried or roasted, a potato rounds out almost any meal. Note that the planting times for potatoes don’t follow the usual pattern. Seed Starting Schedule for Zone 8. The seed packet will usually tell you about when to start seeds in zone 8.