Emerald Blue is a creeping phlox that turns into a solid sheet of lavender-blue bloom for a few weeks each spring, the kind you see cascading over walls and mailbox beds all over town. The rest of the year it is a dense, needle-leaved mat a few inches tall that holds its foliage through most of our winter.

Plant it in full sun with good drainage: slopes, rock gardens, wall tops, and bed edges are its natural habitat. Once rooted in it handles drought, dry rocky soil, and deer without complaint. Shear it lightly after flowering to keep the mat tight and encourage fresh growth.