Perennial hibiscus (Hibiscus moscheutos) is commonly known as rose mallow or dinner plate size hibiscus. Blooms measure a huge 7-9 inches across. Plants are exceptionally hardy, and can withstand winters as cold as zone 4 (-20°F to -30°F) in Minnesota (zone 4) and the heat of zone 9 (20°F -30°F) in Florida. Each flower lasts […]