Westringia fruticosa, coast rosemary or Australian rosemary, is an evergreen shrub native to the coastal cliffs and dunes of eastern Australia, named for its resemblance to true rosemary (Salvia rosmarinus) despite being unrelated — a member of the mint family by way of the figwort tribe, not a culinary herb. Small, needle-like, gray-green leaves with silvery undersides cover a naturally neat, rounded mound, studded nearly year-round in mild climates with small white to pale lavender flowers that draw bees and other pollinators without ever putting on a dramatic show.
Its defining trait is an unusually high tolerance for salt spray, wind, and sandy or poor soil, developed growing directly on exposed Australian coastlines — making it a mainstay of seaside landscaping wherever it's hardy, and a natural fit for a gravel or Mediterranean-style planting even well away from the coast. It is not reliably frost hardy and struggles outside roughly Zone 9, so in colder climates it is grown in containers and moved under cover for winter. Full sun and sharp drainage keep it densest and most floriferous; it shears readily into a formal hedge or low border but also looks equally at home left to its naturally rounded, informal shape, needing only an occasional light trim to stay tidy.
Root rot
Plants wilt, yellow, and stunt even in moist soil; lower stems and roots turn brown, soft, and mushy and the plant may collapse. Most common in heavy, wet, or poorly drained ground.
Improve drainage and stop overwatering, and never plant too deep. Lift and destroy badly affected plants along with the soil around the roots. Grow in raised or free-draining beds to prevent it returning.