Achillea millefolium: Medicinal properties and complete growing guide for yarrow

Introduction to yarrow (Achillea millefolium)

The yarrow, scientifically known as Achillea millefolium, is a perennial herbaceous plant recognized not only for its beauty and adaptability in gardens, but mainly for its very wide medicinal properties and its extensive tradition in phytotherapy in Europe and other temperate regions of the planet. This species, from the family of the Asteraceae or Composite, grows wild on slopes, meadows, grasslands, roads and edges of fields, developing in rich, moderately fresh and well-drained soils.

Yarrow has earned popular names such as yarrow, yarrow, millefeuille, feather duster o soldiers' grass due to both the legends about its use in ancient times and its practical uses and complex, branching morphology. Its botanical name honors Achilles, the Greek hero who used it, according to mythology, to heal the wounds of his soldiers. The epithet millefolium refers to its finely segmented leaves, which appear to be composed of many small leaflets.

Distribution and ecologyNative to Eurasia and widely naturalized on other continents, yarrow is a species subcosmopolitan, adapted to altitudes reaching up to 2500 meters, and even withstands conditions of intense cold and drought once established.

Botanical characteristics of yarrow

• Ports: Perennial herbaceous plant between 15 and 90 cm tall, with erect, simple or branched stems, often tomentose.
• Rhizome: Horizontal, woody, which allows it to form dense carpets and spread vigorously.
• Sheets: Alternate, bi or tripinnatisect (finely divided to appear almost feathery), fresh green to greyish in colour, with a texture reminiscent of ferns.
• Inflorescence: Small heads, grouped in corymbs or cymes, with white, pink or purple flowers depending on the variety.
• Flowering: From early summer to autumn, lasting until November depending on the weather.
• Fruit: An obovate and compressed achene, without a pappus.
• Aroma: The entire plant is intensely aromatic; the scent is pleasant and distinctive.

Yarrow is also a species attractive to pollinators like bees and butterflies, thanks to the aroma and nectar of their inflorescences.

Common names and etymology

Regional diversity has given rise to numerous popular names, in addition to yarrow and yarrow: hundred in a branch, millefeuille, milfullas, milorri, feather flower, foxtail, soldier's herb, feathery, feathery and others.

Etymology: The term Achillea refers to the legend of Achilles and its use in the Trojan War, while millefolium It refers to the appearance of the leaves, as if they had a thousand leaflets.

Chemical composition and active ingredients

Yarrow stands out for its complex phytochemical composition, with a variety of compounds that give it its multiple therapeutic effects. The main components include:

• Essential oil (0,2–1,4%): Includes azulenes (chamazulene), monoterpenes (camphor, pinenes, eucalyptol, sabinene, camphene), sesquiterpenes (caryophyllene), terpene oxides (cineole, linalool, borneol), monoterpenones (isoartemisiacetone, thujone).
• Sesquiterpene lactones: Such as aquilicin, aquiline, matricin, leucodin, milefin, aquilifolin, dihydroparthenolide.
• Flavonoids: Rutin, apigenin, luteolin, isorhamnetin, artemetin, casticin and their heterosides.
• Tannins: Mainly catechics (3-4%) and other types, responsible for its astringent and healing effect.
• Phenolic acids: Salicylic acid, caffeic acid and their derivatives.
• Coumarins: Approximately 0,35%.
• Saponins, resins and polyynes.
• Alkaloids: Betaine, aquicein, aquilein, stachydrine, glycine betaine (usually in traces).
• Plant sterols: β-sisttosterol, stigmasterol, campestrol.
• Vitamins: Vitamin C, folic acid.
• Minerals: Mainly potassium.
• Lipids: Triglycerides of linoleic, oleic and palmitic acids.

This complex synergy of antioxidant, anti-inflammatory, astringent, bitter, antispasmodic, and vulnerary components explains yarrow's versatility in the therapeutic field.

Medicinal properties of yarrow

La Achillea millefolium It is one of the most highly valued plants in traditional and modern medicine, being officially recognized in pharmacopoeias and validated by scientific literature. Its uses include both internal and external treatments thanks to the variety of its pharmacological actions.

Internal uses

• Anti-inflammatory: Chamazulene, sesquiterpene lactones, and flavonoids are involved in reducing inflammation, with efficacy on both the digestive tract and soft tissues.
• Spasmolytic: It relaxes the smooth muscles of the digestive system and uterus, ideal for relieving colic, gastrointestinal spasms, menstrual pain, and cramps.
• Bitter-eupeptic and carminative: It enhances appetite and digestion by stimulating gastric and biliary secretions. Its bitter compounds, especially sesquiterpene lactones, make it useful for anorexia and dyspepsia.
• Choleretic and cholagogue: It stimulates the production and evacuation of bile, useful in hepatobiliary disorders such as biliary lithiasis, biliary dyskinesia, cholecystitis, cholelithiasis and slow digestion.
• Astringent and antihemorrhoidal: Due to its abundance of tannins, it is beneficial for diarrhea, hemorrhoids, varicose veins, and light bleeding, contributing to the reduction of inflammation and vascular comfort.
• Hemostatic: It stops small internal hemorrhages, thanks to compounds such as aquiline and tannins.
• Mild hypoglycemic: Sesquiterpene lactones help regulate glucose levels, being an adjuvant in type II diabetes.
• Emmenagogue: It promotes menstrual regularity and is useful for dysmenorrhea, amenorrhea and mild metrorrhagia.
• Antibacterial and virucidal: Proven effect against bacterial agents and viruses (including hepatitis B virus in studies).
• Expectorant: Useful for mild respiratory conditions.
• Diuretic, mild hypotensive and febrifuge: It stimulates the elimination of fluids and can help moderately control fever and blood pressure.
• Vermifuge, anticonvulsant and antirheumatic: Other documented traditional effects.

External uses

• Astringent and hemostatic: Stops minor bleeding and promotes tissue contraction.
• Healing and vulnerary: Yarrow is famous for its ability to promote Skin regeneration in wounds, ulcers, burns, sores, and dermal ulcerations.
• Antihemorrhoidal and anti-inflammatory: It is used in sitz baths to relieve hemorrhoids, menstrual cramps, pelvic discomfort and proctological conditions.
• Hair tonic: In lotions and shampoos it stimulates hair growth and prevents dandruff.

Other applications include use in creams, masks, and toners for combination or oily skin.

Recognized therapeutic indications

• Digestive disorders: gastritis, dyspepsia, spasms, nausea, vomiting, flatulence
• Hepatobiliary disorders: biliary dyskinesia, lithiasis, cholecystitis and cholelithiasis
• Menstrual irregularities: amenorrhea, dysmenorrhea, metrorrhagia
• Circulatory problems: varicose veins, phlebitis, hemorrhoids
• Adjuvant in type II diabetes, fever, common cold, venous conditions
• Skin diseases: wounds, ulcers, dermatitis, burns
• Sitz baths for pelvic spasms and menstrual pain
• Hair treatment for dandruff and hair loss

Preparations and methods of use

Infusions and herbal teas

Yarrow infusion is one of the most popular, indicated for menstrual cramps, liver and digestive disorders, and fluid retention.

1. Digestive infusion: 2 to 4 g of dried flowering tops per cup of hot water, taken up to three times a day.
2. Diuretic herbal tea: Mix yarrow with sandwort, horsetail, and corn silk (in equal parts); boil two tablespoons in half a liter of water, let it steep for 15 minutes, and consume throughout the day. Do not use if you are taking medication for high blood pressure or heartburn.
3. Infusion for menstrual pain: Combine yarrow, sage, horsetail, and lemon balm leaves, one tablespoon per cup. Drink two cups daily in the days leading up to your period.

Decoction and external use

For wounds, ulcers, mouth sores and hair use:

1. Boil yarrow and other vulnerary plants (comfrey, calendula, cat's tail) for 2 minutes, let stand for 20 minutes and strain.
2. Apply it to the wound with gauze or a small bottle, reapplying it several times a day.
3. For oral conditions, rinse or gargle.
4. As a poultice, apply the boiled leaves and flowers to the wound to promote healing and stop minor bleeding.

Sitz baths

For pelvic discomfort, hemorrhoids, or menstrual cramps, prepare sitz baths with 100 g of dry drug in 20 liters of hot water.

Trade forms and other uses

• Liquid extracts, capsules, tinctures, and creams are available in herbalists and pharmacies.
• Hair lotions, shampoos, ointments and soaps.

The dosage should be adjusted to the preparation and it is always recommended to consult a qualified healthcare professional.

Precautions, side effects and contraindications

Despite its wide safety margin, it is essential to observe these Precautions:

• contraindicated in cases of hypersensitivity to plants of the composite family (Asteraceae).
• Do not use during pregnancy due to its potentially uterotonic action.
• Avoid during breastfeeding due to the lack of studies on the excretion of its active ingredients in breast milk.
• In hypersecretory dyspepsia or biliary obstruction (may increase the production and output of bile, worsening the condition).
• Possible interactions with oral anticoagulants and drugs that decrease gastric acid production.
• Do not prescribe prolonged treatments without professional supervision.
• External use: In sensitive individuals, the fresh plant may cause contact dermatitis (due to the sesquiterpene lactones and polyynes); there is a risk of photosensitivity and allergic reactions (hives, rashes).
• In rare cases, headaches, dizziness, seizures, and glomerulonephritis have been reported with excessive use.

No adverse reactions have been documented at the recommended doses and during short courses of treatment.

Scientific studies and official recognition

Yarrow has been the subject of numerous scientific investigations:

• In vitro and in vivo studies on their anti-inflammatory, antispasmodic, hypoglycemic, antimicrobial and antiviral effects (including hepatitis B virus).
• Studies on the antitumor activity of aquiline acids against leukemic cells in animal models.
• Research on the antipyretic, liver-protective and cardiovascular effects.
• Literature collected in monographs of the European Pharmacopoeia and recognized by organizations such as the German Commission E and the WHO.
• Numerous clinical trials and indexed publications support the safety and efficacy of its main uses.

Its traditional use as relevant medicinal plant It has been complemented by the support of modern phytotherapy, emphasizing the importance of always using pharmaceutical-quality raw materials that meet official standards.

Growing Yarrow: A Detailed Guide

Yarrow is an excellent choice for both ornamental gardens and home medicinal use:

Soils and exposure

• Prefers substrates light and fresh, with a certain amount of moisture but well-drained soils; it thrives in poor, dry, calcareous, and even clayey soils if they are not heavy or excessively wet. To expand your knowledge of aromatic plant care, you can also visit plants to create a sustainable garden.
• Tolerance: It tolerates drought, intense cold and lack of water once rooted. Ideal for massifs, borders, rockeries, slopes and inclines for its resistance and upholstery function.
• Thrives in full sun or partial shade and can grow under tree canopies.

Sowing, planting and propagation

• Sowing and planting: It can be done from spring to late summer.
• Cuttings: It is easily propagated by dividing rhizomes or stolons, especially in early spring or fall. Each plant can produce multiple shoots in a single year.
• Planting density: It is recommended to leave at least 50 cm between plants, guaranteeing one square meter to ensure sufficient quantity of flowers for annual family medicinal use.
• Once established, it forms a dense carpet that competes effectively against weeds thanks to its allelopathic effect (makes it difficult for unwanted vegetation to grow).

Irrigation and fertilizer

• Regular watering the first year. Subsequently, once well established, it can withstand several weeks of drought.
• Fertilization: Organic fertilizer (compost, humus) in autumn-winter, mineral fertilizer in spring.

General care

• Removing faded flowers encourages reblooming throughout the season.
• It can withstand very low temperatures if the soil does not remain waterlogged.
• It is resistant to pests and fungal diseases.

Harvesting and drying

• Part used: Flowering tops (flowers and upper part of stems).
• Harvest at the beginning or during full flowering, preferably on dry and sunny days.
• Dry in a well-ventilated, shaded area to preserve essential oils. Store in airtight containers and protect from light.

Ornamental and ecological uses

• Decorates perfectly borders, flowerbeds, slopes, rockeries and dry gardens.
• Due to its rhizome, it can be used as upholstery and earring fixer or eroded soils.
• Cut and dried flowers are used in long-lasting floral arrangements and herbalism.
• It attracts pollinators, promoting the biodiversity of the garden.

Additional tips for growing yarrow

• Rotation and expansion: If left unchecked, yarrow can quickly colonize large areas, but it is easy to maintain by pruning and dividing rhizomes.
• Pot cultivation: It is possible if you ensure a good-sized container and regular watering.
• Yarrow tolerates transplanting well, but it is advisable to transplant before frost arrives to ensure proper rooting.
• Controlling dead flowers and cutting them back in the fall will revitalize the plant the following season.

Contraindications and expanded precautions

In addition to the warnings already mentioned, it is important to know:

• Hypersensitivity and allergies: Caution in people allergic to other Asteraceae (e.g., ragweed, chrysanthemum, daisy, dandelion) due to risk of cross-reactivity.
• In particularly sensitive individuals it can cause dermatitis, urticaria or photosensitivity by contact with the fresh plant or essential oils.
• Chronic or high-dose use should never be undertaken without competent professional supervision.
• Avoid self-medication if you are taking anticoagulants, anti-inflammatories, antihypertensives, digestive medications or if you suffer from serious chronic illnesses.
• It is not suitable for pediatric population without medical advice.

Recent research and modern applications

• Multiple scientific publications, double-blind placebo-controlled clinical trials and in vitro studies support the properties of yarrow, highlighting its mechanisms of action as an inhibitor of cyclooxygenase and 5-lipoxygenase, key in inflammation.
• Its antimicrobial effect has been studied in essential oils and methanolic extracts, with activity against bacteria, fungi and viruses.
• Research on its ability to reduce blood glucose, modulate liver and antioxidant markers, and its potential as an adjuvant in liver disease and chronic inflammatory diseases.
• Aquilinic acids and chamazulene exhibit antitumor and cytotoxic activity in preclinical models, paving the way for future pharmacological applications.

Frequently Asked Questions About Yarrow

• Can yarrow be consumed daily? Yes, as an infusion and in recommended doses, for short periods and without a history of allergies, pregnancy, or breastfeeding.
• Can yarrow be planted in warm climates? It is a very adaptable plant that thrives in both cold and warm climates if it receives enough sun and non-waterlogged soil.
• What part of the plant is used medicinally? Mainly the flowering tops, that is, the floral heads and upper stems collected while flowering.
• How to preserve yarrow? Dry quickly after harvesting in a shaded, airy place and store in opaque, airtight jars to preserve their essential oils.

Tips for safe and effective use

• Always consult with a healthcare professional before starting yarrow treatment, especially if you are taking other medications or have chronic illnesses.
• Respect the recommended doses and do not prolong use beyond what is suggested in phytotherapy.
• Do not use during pregnancy, breastfeeding, during young children, or in cases of severe allergies to compounds.
• If you experience any adverse reaction, discontinue use and consult a specialist.

La Achillea millefolium It is a true gem of European and international herbal medicine, combining a long medicinal tradition with modern scientific evidence. Thanks to its easy cultivation and extraordinary therapeutic and ornamental versatility, it is one of the essential plants in natural medicine cabinets and low-maintenance gardens. Adopting yarrow in your home, whether to relieve digestive, menstrual, or skin discomfort, or simply to enjoy its beauty and resilience, brings ancient wisdom and current evidence into our daily lives.