Trendy landscape designers like to set flagstone walkways slightly out of step to compel visitors to the garden to stroll through a bit slower. Between the stones, it is in style to grow creeping thyme, Thymus spp., as a very shallow groundcover that relinquishes its delightfully herbal aroma with any misstep. It stays too low to trip on, tolerates a bit of trampling, and needs only minor trimming where it creeps a bit too far onto stones or pavement. Creeping thyme can also be plugged into retaining walls of broken concrete or stone. The grayish green foliage is very finely textured. While the weather is warm, minute lavender flowers bloom in subdued phases that come and go slowly. Some varieties have more pinkish flowers, lighter green foliage or exhibit different aromas.