Rosemary (Rosmarinus officinalis) ‘Arp’ is winter hardy in southern Appalachian (USDA hardiness zones 6-b and 7-a) gardens for two decades , including some very cold winters. Other rosemary cultivars which have succeeded include ‘Athens Blue Spires’, ‘Hardy Hill’, and ‘Salem’.
Locate a site with a “micro-climate” advantage such as next to a driveway or along the southside of a red brick home or a dark colored garage wall. Here winter temperatures vary by a few degrees warmer. Dark asphalt pavement absorbs and retains heat. Next to large bodies of water, such as a swimming pool and a water garden, may also be slightly warmer in the winter.
Plant rosemary in well-drained soil and in full direct sunlight. With rosemary and other semi-tender herbs, winter kill may also be caused by wet, soggy soil rather than cold.
‘Arp’ matures a handsome woody shrub with fine textured foliage. It grows 3-4 feet tall and wide, and blooms in early spring. The blue flowers are small and attract lots of insect activity.