Thymus vulgaris Seeds | English Thyme
LATIN NAME: Thymus vulgaris
COMMON NAME: Common Thyme
Plant Profile
Thyme is a small woody subshrub that behaves like a herb and ages like a shrub. Thymus vulgaris comes from the dry hills of the western Mediterranean, and it keeps the habits of that origin: a deep taproot, a low dome of wiry stems 20-40 cm high, and leaves so small and thick-coated that they lose almost no water. Growth is slow and deliberate rather than lush.
The plant is also more variable than the name suggests. Wild thyme populations differ in the dominant essential oil, and growers recognize at least six chemotypes, among them thymol, carvacrol, geraniol, linalool and thuyanol types. They look nearly identical and smell entirely different, which is why two packets labelled Thymus vulgaris can produce plants that a chef would call different herbs.
Science & Biotechnology
Thymol is the compound that made thyme famous, and its history runs through the founding of antiseptic surgery: Lister tested thymol among the phenolic agents he used to clean wounds and instruments in the 1860s. The mechanism is now well described, since thymol and its close relative carvacrol disrupt bacterial membrane integrity, and both show activity against a range of food-borne organisms in laboratory work.
The chemotype question is where the research gets more interesting for growers. Oil composition is partly genetic and partly a response to stress, so a plant grown rich and watered will often produce less thymol than the same clone kept dry and lean. Thyme is also the subject of drought-tolerance work, because its stomata and leaf anatomy let it keep photosynthesizing at water potentials that would close down most herbs.
Uses & Benefits
In the kitchen thyme is one of the few herbs that improves with cooking, which is why it anchors stocks, braises and bean dishes rather than finishing them. The leaves hold their flavour through long heat, and the woody stems can go into a pot and be fished out later.
In the garden its jobs are quieter. The flowers open in early summer and are worked by honeybees and a long list of solitary bees at a moment when little else is open. The dense mat suppresses weeds, tolerates being walked on, and holds a bank or the edge of a path where mowing is awkward. Thyme also has a documented place in European medicine for productive coughs, with thyme preparations listed in the EMA monographs for bronchial catarrh.
Growing from Seed
Surface-sow onto a mix that is more grit than compost, because the seed is small and light is part of the trigger. Press it into the surface and do not cover it, then keep the tray at 15-20°C with steady moisture from below. Germination takes ten days to three weeks, and the first growth is so fine that it is easy to mistake for moss.
Thyme seedlings resent being pricked out small; wait until each has three or four true leaves and lift them in clumps with a dibber rather than teasing roots apart. Grow them on in individual cells, keep them cool and bright, and plant out in early summer. After the first year, shear the plants back by a third immediately after flowering; cutting into the old wood below the leaves will kill them, and this is the single mistake that shortens most thyme plants’ lives.
Our Take
Buy seed by chemotype if you can, and if you cannot, smell the seedlings before you plant them. A thymol type is what most cooks mean by thyme; a geraniol type tastes floral and slightly odd in savoury food. Neither is wrong, but only one is what you wanted.
Related Reading
More species in the same orbit as Common Thyme: