Thymus serpyllum "Aureus," or yellow transparent thyme, is the prettiest thyme I have ever grown.  I love all thyme varieties and not just for the delicate flavor they lend to all kinds of dishes, but also because of the different foliage colors, stem colors, flower colors, delicious scents, and various growing habits.  This is probably my favorite to look at because of its chartreuse color that stands out in the garden and brightens gray days and makes the sunny ones even more dazzling.  Yellow transparent thyme has a creeping habit, rather than upright, and makes a beautiful accent in either the perennial border or the herb garden.  "Aureus" has excellent flavor and thrives in dry soil, so don't over water - thyme doesn't appreciate it.   Zones 5-8.

This lemon-scented, variegated thyme is perfect for the alpine, rock, or herb garden.  Growing from two to six inches in full sun and average, well-drained soil, "Doone Valley" is sure to please with its variegated gold and deep green scented leaves, which are more pronounced in spring.  In mid-summer and fall, the leaves are more green, letting the rose pink flowers that are enjoyed by butterflies and bees take center stage (see photo below).  Full sun, drought tolerant in Zones 4-9.