THYME: CHARACTERISTICS, HABITAT, PROPERTIES, CULTIVATION - BIOLOGY - 2025

The thyme (Thymus) is a genus of shrubs or perennial herb belonging to the family Lamiaceae. Made up of approximately 350 species, it is native to temperate regions of Europe, Asia, and North Africa.

The plant is a branched aromatic herb with a semi-woody, sinuous and pubescent stem that reaches 20-50 cm in height. The square section stem is covered by small clustered 4-5 mm leaves with a green-gray hue and a hirsute appearance.

Thyme. Source: pixabay.com

The small bilabiated flowers of pink or soft color are arranged in firm and dense terminal heads. Flowering occurs during the months of March and May, depending on the altitude and environmental conditions.

In the wild, thyme is located on arid, dry and even intervened soils, since they require low amounts of water and nutrients to develop. They are located in association with bushes in full sun exposure, being able to withstand direct sunlight due to the oily condition of their leaves.

Different members of the genus, such as the species Thymus albicans, Thymus vulgaris or Thymus zygis are cultivated as a dressing, medicinal plant or ornamental plant. When rubbed, they give off an aroma of great intensity that varies according to the species, its main components being thymol p-cymene, linalool and carvacrol.

The largest thyme production is used for medicinal, gastronomic and ornamental purposes. In addition to being used as healing agents, it is used to flavor water or oil, and as an alternative to incense in ancestral ceremonies and rituals.

General characteristics

Estate

The root system is made up of a taproot of the pivoting type covered by abundant secondary roots. Certain species of creeping or stoloniferous growth develop roots from the nodes, which favors their fixation to the ground.

Stem

The various species that make up the genus Thymus have a herbaceous or semi-woody stem up to 50 cm tall. This lively, woody, highly branched and evergreen structure can have an erect or decumbent growth.

Leaves

The simple, opposite, seated leaves, oblong or lanceolate, are 3-5 mm long by 0.5-1.5 mm wide. Their margins are whole and twisted, the leaflets are tomentose and aromatic, of a dull gray-green color on the upper surface and whitish on the underside.

Thymus leaves. Source: pixabay.com

flowers

The small pink or whitish axillary flowers are grouped in inflorescences forming a kind of terminal chapter. The flowers are bilabiated with the corolla slightly longer than the calyx, the upper lip raised and the lower lip trilobed.

The slightly tomentose green-gray bracts, the calyx gibbous and ciliated, and four obvious stamens protrude from the corolla. Flowering occurs mainly during spring, being a species with excellent melliferous properties.

Fruit

The fruit is tetrachenium consisting of four achenes or dry indehiscent, glabrous and dark brown nucules. These fruits do not have any ornamental interest.

Chemical composition

Chemical analysis of the Thymus vulgaris L. and Thymus zygis L. species indicates the presence of essential oils and flavonoids. However, its content and purity is determined by the age of the plant, place of sowing and harvest time.

The main essential oils (1-2.5%) are identified as the monoterpenic phenols borneol, carvacrol, gamma-terpinene, limonene, linalol, p-cymene and thymol. Regarding flavonoids, the presence of apigenin, cirsilineol, cirsimaritin, eriodictol, luteolin, naringenin, salvigenin, timonin and thymusin is noted.

In addition, it is common to detect significant amounts of the phenolic acids caffeic and rosmarinic, vitamins A, B ₁ and C. Likewise, saponins, tannins, the alcohols gerinol, linalol and terpinol, the triterpenes ursolic acid and oleanolic acid, and a bitter principle called serpylin.

Nutritional value (per 100 grams)

- Calories: 350-420 kcal

- Proteins: 9-10 gr

- Fats: 7.2-7.8 gr

- Fiber: 18-20 gr

- Carbohydrates: 55-58 gr

- Calcium: 1,850-1,900 mg

- Phosphorus: 210-220 mg

- Iron: 120-125 mg

- Magnesium: 220-225 mg

- Potassium: 810-815 mg

Taxonomy

- Kingdom: Plantae

- Division: Magnoliophyta

- Class: Magnoliopsida

- Order: Lamiales

- Family: Lamiaceae

- Subfamily: Nepetoideae

- Tribe: Mentheae

- Genus: Thymus L. 1753

Thyme inflorescences. Source: pixabay.com

Etymology

- Thymus: the name of the genus comes from the Greek words "thymon" and "thymos", the original name of these plants. On the other hand, its designation derives from the word "thyein" which means aroma and smell.

Synonymy

- Mastichina Mill. (1754)

- Serpyllum Mill. (1754)

- Cephalotos Adans. (1763)

Habitat and distribution

The natural habitat of this species is located in dry and warm environments, in association with wild scrub or Mediterranean thyme. It grows on different types of substrates, preferably soils of calcareous, sandy, stony origin, well drained and not very fertile.

Indeed, despite their wide adaptation to different types of soil, it is essential that they have good drainage and do not get flooded. They are located on sandy soils, from sea level to a maximum limit of 2,000 meters above sea level.

Most species of the genus Thymus are cultivated plants native to the western region of the Mediterranean basin. It is also located in North Africa and some regions of the Middle East.

In Europe it is common in the regions bordering the Mediterranean, although it is widely distributed throughout Central Europe. It is widely cultivated as an aromatic shrub in southern Italy, Tin, France, Morocco, and some areas of the United States and Mesoamerica.

It is a native shrub of Mediterranean ecosystems characterized by warm seasons and low rainfall. In general, this genus adapts to different environments, particularly in holm oak forests, bushes, meadows and on the edge of roads.

The representative species of the genus is Thymus vulgaris known as common thyme, being used as a condiment or medicinal plant. Some species are endemic to the Mediterranean coast of the Iberian and Italian peninsulas, as well as to Morocco and Tunisia.

Thyme in its natural habitat. Source: pixabay.com

Properties

Thyme is an aromatic plant that has various culinary, medicinal and ornamental properties. Its branches, leaves and flowers have been used in a traditional way to alleviate various symptoms and ailments since ancient times.

Thyme is consumed as a tea or infusion to calm colic, diarrhea, intestinal gas, nocturnal enuresis and intestinal discomfort. It also relieves sore throat, whooping cough and bronchial problems, as well as pain caused by arthritis.

On the other hand, it is used to disinfect the urine, as a diuretic or dewormer, and as an appetite stimulant. Topically, it is applied directly to soothe skin irritation, reduce inflammation of the tonsils, against laryngitis, inflamed gums and bad breath.

Of the group of plants that make up the genus Thymus, only the species Thymus vulgaris, Thymus mastichina, Thymus serpyllum, and Thymus zygis are of commercial importance. Fresh or dried herbs are used from the plant, either as infusions or a source of essential oils for creams and fomentations.

Antibacterial activity

Thymol (2-isopropyl-5-methylphenol) is a substance present in the essential oils of thyme (Thymus vulgaris) that helps prevent tooth decay. Indeed, the essential oils of thyme are used as bactericides to prevent infections of the mouth and scalp.

Antispasmodic and expectorant activity

Thyme has antispasmodic activity in the respiratory tract and acts as a relaxant of the bronchial smooth muscle, exerting an antitussive effect. This effect is favored by substances such as carvacrol or thymus in its essential oils, as well as the spasmolytic action of flavonoids.

In fact, the great complexity of essential oils improves the activity of the bronchial cilia, favoring their expectorant action. The production of bronchial-alveolar secretion is increased, thus the fluidization of bronchial secretions occurs, which favors their expulsion.

Anti-inflammatory activity

The topical application of macerates, plasters or ointments made from the essential oil of thyme relieves rubefacient symptoms of the skin. Indeed, thyme essential oil is used in the preparation of liniments used for the treatment of muscular and osteoarticular discomfort.

Antioxidant activity

Thyme has an anti-radical action, that is, it acts as an antioxidant substance, reducing the production of free radicals. Carvacrol and thymol present in essential oils, as well as polyphenols and flavonoids, act in this work.

Thyme oils and essences have medicinal properties. Source: pixabay.com

Antiseptic activity

The cooking of thyme branches has antiseptic effects (bactericidal, fungicidal and virucidal), due to the presence of phenolic compounds, carvacrol and thymol. This effect is the result of the adverse action of these phytochemical elements on the cell membrane of germs.

War activity

The ingestion of an infusion of thyme cleans the respiratory tract, prevents bacterial growth and acts as an effective antispasmodic. Indeed, it has an antitussive effect, since it acts directly on the medulla oblongata, suppressing the cough reflex.

Estrogenic activity

It has a certain estrogenic effect, since its intake is similar to the female sex steroid hormone estradiol which acts on the symptoms of menopause. Due to this action, its use is suggested in the prevention of diseases associated with excess xenoestrogens, such as breast cancer.

Eupeptic activity

The habitual consumption of decoctions or foods flavored with thyme favors the digestion process. Thyme is used as an aperitif, carminative and digestive, as it stimulates the appetite, regulates the expulsion of gases and promotes digestion.

Culinary use

Thyme is an aromatic herb traditionally used in Mediterranean cuisine as a condiment or in the preparation of pickles. Thanks to its characteristic aroma and flavor, it is used as a dressing or dressing in stews, pickles, marinades and grills.

In Spain, thyme is an essential ingredient for the Catalan soup "farigola" and is commonly used as a marinade in Extremadura cuisine. In France it is an ingredient of the «bouquet garni» and is part of the group of Provencal herbs used in gastronomy.

Thyme is used as a garnish for various sauces. Source: pixabay.com

In Italy, it is used in the famous "focaccia"; in the Middle East it is used as an aromatic herb for the seasoning called "zata'ar". In the United States, it is one of the special ingredients of Kentucky-style chicken, where thyme brings a particular fragrance to the preparation.

In general, its use favors the preservation of food due to the antioxidant and antimicrobial properties provided by carvacrol, thymol and flavonoids. In addition, its fresh or dry use provides particular organoleptic characteristics and favors digestive processes.

Contraindications

It is not recommended ingestion during pregnancy or lactation without medical supervision. Natural products are therapeutic aids for the treatment of a disease, they are not a substitute for symptomatic treatment.

Culture

The different commercial species of the genus Thymus can be propagated by seed. The sowing is done in nursery conditions on a fertile substrate, maintaining the temperature and humidity conditions, the seeds take 8-20 days to germinate.

Similarly, it can be reproduced vegetatively by dividing adult plants. Usually, 20-30 seedlings are obtained from a mother plant, these are rooted in a humid medium and then transplanted to the final site.

Transplantation is recommended when the plant reaches 8-10 cm in height and has developed true leaves. In the case of plant division, transplantation is carried out when the plant has developed a strong and vigorous root system.

Seedling management requires great care in order to avoid physical damage to the roots. A suitable tool is used to remove the seedlings from the seedbed and place them in a container, bag or pot with a fertile and moist substrate.

Requirements

Thyme adapts to different climatic conditions, despite being resistant to frost, its ideal climate is the Mediterranean. The best yields are obtained with full sun exposure in warm and moderately dry environments, sunny summers and mild winters.

During spring and early summer it requires average temperatures of 20-30ºC. In the development phase, a soil temperature above 18ºC favors its growth and the regeneration of the crop after harvest.

It grows on fertile soils, of calcareous origin, light, sandy loam and well drained, with a pH range of 5-8. Drainage is essential for the productivity of the plant, waterlogged soil tends to cause rotting of the root system.

Almacigo of Thymus vulgaris. Source: Forest & Kim Starr

Driving

Thyme is a drought resistant plant, so it does not require frequent watering to develop in a healthy and vigorous way. However, it is a crop that requires frequent applications of organic matter or a chemical formula to meet its nutritional needs.

This aromatic shrub does not require frequent pruning, since the important thing is to produce abundant branches that provide green material. However, they are usually invaded by weeds, which compete for space, light, water and nutrients, hence the importance of permanent control.

The best yields are obtained from the second year after sowing, until approximately the sixth year. The harvest consists of collecting branches 15-20 cm long, the collected material needs to be processed immediately if the essential oil is expected to be obtained.

For culinary or medicinal use, the branches are dried in the shade or in tumble dryers at temperatures below 40 ºC. Usually 4-5 tons / hectare of fresh material are obtained, which loses 60-65% of its weight when drying.

Plagues and diseases

Thyme is a rustic plant, resistant to attack by pests and diseases, unless it is weak and susceptible. In this case, it is advisable to avoid humid environments and heavy, poorly drained soils that favor the appearance of fungal diseases.

One of the main pests that tend to reduce the quality of thyme foliage are phytophagous nematodes. The causal agent of the disease is Meloidogyne hapla, which causes yellowing of branches and foliage.

In severe attacks, the nematode destroys the root system causing the death of the plant. Preventive control is carried out through disinfection of the soil, vegetative multiplication through healthy and disinfected feet is also recommended.

In general, it is not appropriate to grow thyme in those fields that have reported the presence of the phytophagous nematode. On the other hand, defoliation and yellowing of the leaves after flowering is common, so it should not be confused with any pathogen or physiopathy.

References

1. Carretero, ME, & Ortega, T. Medicinal Plants with Expectorant activity: Thyme. 9 pp. Department of Pharmacology. Faculty of Pharmacy, Complutense University of Madrid.
2. Gimeno Gasca, JM (2001). Thyme (Thymus vulgaris L.). Naturopathic Medicine, (3), 173-175. ISSN: 1576-3080.
3. The Thyme Plant (2017) Wikifarmer. Recovered at: wikifarmer.com
4. López-Ambrocio, RM, Ruiz-Posadas, LM, & Delgadillo-Martínez, J. (2016). Antimicrobial Activity of Thyme Essential Oil (Thymus vulgaris L.). AGRO.
5. López Luengo, MT (2006). Thyme: Pharmacological properties and therapeutic indications. Offarm: Farmacia y Sociedad, 25 (1), 74-77.
6. Morales Valverde, R. (1986). Taxonomy of the genera Thymus (excluded from the section serpyllum) and Thymbra in the Iberian Peninsula. CSIC-Real Jardín Botánico (RJB).
7. Thymus. (2019). Wikipedia, The Free Encyclopedia. Recovered at: es.wikipedia.org