
Gulf Coast/South
ZONE 28. Gulf Coast, North Florida, Atlantic Coast to Charleston
Growing season: mid-Mar. to early Dec. Humidity and rainfall are year-round phenomena; summers are hot, winters virtually frostless but subject to periodic invasions by frigid arctic air. Azaleas, camellias, many subtropicals flourish.
ZONE 31. Interior Plains of Gulf Coast and Coastal Southeast
Growing season: mid-Mar. to early Nov. In this extensive east-west zone, hot and sticky summers contrast with chilly winters (record low temperatures are 7 degrees to 0 degrees F/-14 degrees to -18 degrees C). There’s rain all year (an annual average of 50″), with the least falling in Oct.
ZONE 32. Interior Plains of Mid-Atlantic States; Chesapeake Bay, Southeastern Pennsylvania, Southern New Jersey
Growing season: late Mar. to early Nov. Rain falls year-round (40″ to 50″ annually); winter lows (moving through the zone from south to north) are 30 degrees to 20 degrees F/-1 degree to -7 degrees C. Humidity is less oppressive here than in Zone 31.