Mother of Thyme (Thymus serpyllum) is a low-growing perennial native to Eurasia, often used as a dense, fragrant ground cover. It is frequently mistaken for the common kitchen herb, Thymus vulgaris. The leaves and flowering parts of Mother of Thyme are generally considered edible and have a long history of use in traditional herbal practices. This species belongs to the Lamiaceae mint family, and while safe to eat, its characteristics differ significantly from culinary thyme.
The Safety and Edibility of Mother of Thyme
Consuming the leaves and flowers of Thymus serpyllum is widely accepted as safe for the general population. The plant is designated as Generally Recognized As Safe (GRAS) by regulatory bodies and has an excellent safety record. Its safety profile is partly due to the comparatively low concentration of aromatic compounds; the essential oil fraction in Mother of Thyme is typically less than one percent.
The leaves can be consumed fresh in salads, dried as a seasoning, or steeped to create an aromatic herbal tea. General caution should be applied when harvesting any plant for consumption, particularly those growing wild. Avoid plants near roadsides, industrial areas, or any location where the soil may be contaminated with heavy metals or pollutants. Ensure the plant has not been treated with pesticides or herbicides, as external contamination is the primary safety concern for garden herbs.
The lower essential oil content, which includes compounds like thymol and carvacrol, makes it milder than culinary thyme. While safe for general consumption, pregnant women and individuals with thyroid disorders are sometimes advised to consult a healthcare provider before using it medicinally or in large quantities. For everyday culinary use, the plant is non-toxic and a safe addition to the diet.
Visual Differences Between Mother of Thyme and Common Thyme
Proper identification is important to ensure you are consuming Thymus serpyllum and not a different ground cover. Mother of Thyme is easily distinguishable from Thymus vulgaris by its distinct growth habit. T. serpyllum is a prostrate species; its stems creep horizontally along the ground to form a dense, low-lying mat, typically reaching a height of only two to five centimeters.
In contrast, common culinary thyme (T. vulgaris) grows as a small, upright, and somewhat woody shrub, often reaching heights between 30 and 45 centimeters. The leaves of Mother of Thyme are noticeably smaller and more delicate, being oval to almost round in shape and measuring only two to five millimeters in length. Culinary thyme leaves are generally larger, slightly more elongated, and appear on wirier, more branched stems.
The flowers also offer a clear distinction. Mother of Thyme produces profuse, vibrant clusters of lilac-pink or purple blooms near the ground in the summer, creating a colorful carpet. Common thyme flowers are typically subtler and appear on the taller, upright stalks. Observing the plant’s texture further helps with identification; Mother of Thyme is soft and cushiony, while the base of culinary thyme feels more woody.
Culinary Applications and Flavor Profile
The flavor profile of Mother of Thyme is significantly more delicate and subtle than the robust, pungent taste of common thyme. It lacks the strong, savory, and sometimes bitter notes characteristic of T. vulgaris, which possesses a much higher concentration of the phenolic compound thymol. Instead, T. serpyllum is described as having milder, sweeter, and sometimes subtly floral notes.
Some varieties of Mother of Thyme may exhibit light undertones of lemon or mint, making it a gentle seasoning. Due to this milder flavor, it is not a suitable substitute for common thyme in recipes that rely on a strong, herbaceous flavor, such as stews or roasts. Its delicate aroma would simply be lost in the cooking process.
The best culinary uses for Mother of Thyme capitalize on its subtle nature and attractive appearance. The fresh leaves and flowers serve well as a garnish for delicate dishes, such as salads, soft cheeses, or egg preparations. It is also valued for making aromatic herbal infusions and teas, where its floral and gentle notes can be fully appreciated. Furthermore, the herb can be infused into honeys or oils to impart a faint, sweet herbaceous essence.