Excerpt - page 381: "... cm) tall, is especially free-flowering. Height: 4 to 12 inches (Cerastium tomentosum) (10 to 30 cm). Spread: 1 to 2 feet (30 to 60 cm). USDA Plant Hardiness Zones 2 to 7; AHS Heat Zones 7 to 1. Larry's Garden Notes More Recommended Snow-in-Summer Cerastiumalpinum subsp. ..."