Wild Thyme

Botanical Profile

Note: The current botanical assignment of rosemary is Salvia rosmarinus; Rosmarinus officinalis remains in common use as a historical synonym.

Note: Wild thyme comprises several closely related Thymus taxa and should not be equated with common thyme.

Thymus serpyllum denotes wild thyme or creeping thyme in the narrower sense, a low-growing aromatic Lamiaceae species. The flowering herb is important as a raw material; it must be distinguished from Thymus vulgaris and other thyme species as well as from species-rich wild-thyme collection complexes.

Thymus serpyllum L. is a low-growing, creeping to ascending aromatic plant of the Lamiaceae. It forms woody, mat-like shoots, small opposite leaves and dense pink to purple inflorescences. The plant grows on nutrient-poor, sunny, sandy or stony sites, in dry grasslands, heaths and open forest margins. Like other Lamiaceae, it possesses glandular hairs in which essential oil is formed. In practice, the name wild thyme may be used for various wild-growing Thymus species or mixed collection origins; precise botanical identification is therefore essential. The raw material typically consists of flowering herb with leaves, flowers and thin shoot portions.

Phytochemistry

Wild-thyme herb contains essential oil, phenolic monoterpenes, monoterpene alcohols, flavonoids, phenolic acids, rosmarinic acid, tannins and other accompanying substances typical of the Lamiaceae. Depending on origin and chemotype, the essential oil may contain varying proportions of thymol, carvacrol, linalool, geraniol, p-cymene, gamma-terpinene and other terpenes. Compared with cultivated Thymus vulgaris, wild origins are often more variable. Rosmarinic acid and other phenolic compounds contribute to the astringent-herbaceous and antioxidant-investigated fraction. Sensorially, wild thyme has a warm, aromatic, thyme-like and sometimes floral-wild profile. Content and composition vary strongly with taxonomic delimitation, site, harvest time, drying and storage.

Traditional Uses

Wild thyme is known in the European herbal tradition as a wild-growing thyme and was used as an aromatic herb in cuisine, household herbalism, herbal teas and rural preparations. Its warm-spicy aroma and taste made it a typical component of aromatic herbal mixtures. In folklore, wild thyme was often perceived similarly to thyme while also being valued as a wild, regionally gathered herb with its own sensory quality. Traditional use relates primarily to the flowering herb. Historical information must be separated from modern product-related statements and depends strongly on the botanical accuracy of the respective source.

Current Research

Research on Thymus serpyllum addresses primarily essential oil, chemotypes, antimicrobial in-vitro models, antioxidant test systems and phenolic accompanying substances. Because wild-thyme raw materials can be taxonomically heterogeneous in practice, unequivocal species identification is a central research issue. Many thyme data are derived from Thymus vulgaris and must not automatically be transferred to Thymus serpyllum. Studies show that site, developmental stage and drying can markedly influence oil composition. For extracts and essential-oil fractions, analytical characterisation of terpene profiles is essential, particularly in phenol-rich chemotypes.

Sources

• Plants of the World Online: Thymus serpyllum L.; Royal Botanic Gardens, Kew.
• Standard references on Serpylli herba, Thymi herba and essential-oil plants of the Lamiaceae.
• Review and analytical literature on Thymus serpyllum, essential oil, rosmarinic acid and chemotypes.