Thymus vulgaris is the source of the herb thyme. It is a native of southern Europe, although it now grows more widely both wild and in cultivation. The essential oil contains thymol, which is often included in pharmaceutical preparations as an antiseptic. The Thyme plant is a small, bushy sub-shrub that grows to around 45 cm tall. The grayish or green leaves are very small (4 to 8 mm long). The white, pink, or violet flowers are borne in rounded or ovoid terminal clusters.

(Vaughan and Geissler 1997)

Thyme is an insect-pollinated perennial, diploid plant. It is gynodioecious. i.e., natural populations include both hermaphrodite and female individuals. Hermaphrodites have large, protandrous (i.e., male parts mature first) flowers producing substantial amounts of both pollen and seeds; females have smaller, shorter-lived flowers with no stamens. Hermaphrodite Thyme plants produce significantly larger flowers than do females. The frequency of females in populations is highly variable. Thyme exhibits a pattern that is uncommon among gynodioecious plant species in that there is a combination of very high female frequency with hermaphrodites having significant female function (more typically, the hermaphrodites in gynodioecious species function largely as males).

(Manicacci et al. 1998; Ehlers and Thompson 2004)