Yarrow
Yarrow
Achillea millefolium
Plant Family
Asteraceae
Botanical Description
Yarrow is a perennial, aromatic herb with a creeping rhizome that allows it to spread efficiently. Its leaves are feathery and deeply divided, giving the plant a soft, lace-like appearance. The stems are typically upright, angular, and covered in fine hairs.
The flowers are small, white to pale pink, and arranged in flat-topped corymbs (a compound umbel-like structure). Each individual flower head is composed of a few tiny ray florets around a cluster of disk florets.
Its characteristic scent is pungent, resinous, and camphoraceous, especially in warmer climates or when freshly crushed.
Cautions
Yarrow is generally safe when used in moderate amounts. However:
Pregnancy: Due to its mild uterine-stimulating effects, it should be avoided during pregnancy, especially in the first trimester.
Allergies: Some individuals may experience skin rashes or contact dermatitis, especially if allergic to other Asteraceae family plants (e.g. chamomile, ragweed).
Topical Use: Patch test recommended before applying to broken skin.
Blood Thinners: Caution advised for people using anticoagulant medication.
Discontinue use if signs of allergic reaction occur, such as rash or itching.
(Source: Rosemary Gladstar, 2012)
Habitat
Prefers dry meadows, grassy slopes, and sandy or well-drained soils
Tolerates a wide range of conditions, including coastal exposure, drought, and poor soil
Thrives in semi-cultivated areas, wastelands, and along roadsides
Harvest Months
May, June
Root Harvest Time
Spring, Autumn
Geographic Distribution
Yarrow is native to temperate regions across the Northern Hemisphere, including Iceland, Europe, Asia, and North America. It is especially well-established in Iceland, particularly in the north and northeast, where it grows wild in meadows and grasslands. In other parts of the country, it is commonly found near settlements and pastures.
Sustainability Notes
Yarrow is widely distributed, resilient, and easy to propagate. It is not considered endangered and has low ecological risk when harvested responsibly. Still, it’s best to gather only from clean, unsprayed areas and to avoid overharvesting from small patches.
Plant Size
Typically ranges from 15 to 40 cm in Icelandic climates, but can reach up to 90 cm in milder climates.
Harvest Instructions
Harvest aerial parts just before flowering (late May to early June in Iceland)
Cut only the top third of the stem where the leaves and developing flower heads are most potent
Dry in small bundles upside down in a dark, well-ventilated space
Store dried herb in airtight jars away from light and moisture
Pests & Diseases
Yarrow is generally disease-resistant and not prone to pest infestation. It can be susceptible to powdery mildew or rust in overly humid conditions but is otherwise hardy and easy to cultivate.
Cultivation & Propagation
Easily propagated by seed, division, or root cuttings
Grows best in full sun and moderately dry, well-drained soil
Avoid overly rich soil, which may reduce essential oil concentration
Can spread aggressively — consider controlling via containers or borders
Plant Parts Used
Stem, Leaves, Flowers
Effects on the Body
Astringent: Tones and tightens tissues, useful for wounds and mucous membranes
Hemostatic: Reduces bleeding (internal and external)
Vasodilating: Improves peripheral circulation
Carminative: Eases gas and digestive discomfort
Diaphoretic: Induces sweating, helpful in fevers
Antispasmodic: Relieves cramps, especially uterine
Mild Sedative: Calms the nervous system
Yarrow is traditionally used for:
Menstrual regulation
Wound healing
Reducing fever in colds/flus
Circulatory support
Blood pressure balance
Digestive support
Active Constituents
Essential oils: Cineole, azulene, eugenol, thujone, pinene, camphor
Glycosides: Bitter principles, cyanogenic glycosides
Tannins: Astringent compounds
Flavonoids: Apigenin, luteolin (anti-inflammatory, antioxidant)
Alkaloids, salicylates, asparagine, choline, and isovaleric acid
Dosage
Infusion (tea):
1 tsp dried herb per cup of hot water
Steep 10–15 minutes, covered
Up to 3 cups per day
Tincture:
1–3 ml, 2–3x daily
Use 1:5 tincture in 40% alcohol
Poultice or Compress:
Use fresh leaves, lightly crushed, applied directly to clean wounds
Culinary Use
While not common in food today, yarrow leaves were once used in traditional Nordic brewing (like gruit ales). Young leaves can be added in very small amounts to soups or stews but may be too bitter for regular consumption.
Folklore & Historical Use
Yarrow has a long tradition as a folk remedy in Icelandic, European, and Asian medicine.
In Grasnytjar (1781), Björn Halldórsson described yarrow as "one of the best wound-healing herbs" used to treat both external and internal bleeding. The decoction was especially praised.
In 1860, Alexander Bjarnason referred to it as one of the most versatile healing herbs, calling it strengthening, resolving, and blood-purifying.
Historically, it was used to treat colic, vomiting, and urinary retention, as well as joint stiffness and tight tendons. It was also added to ointments and wound salves.
References
Icelandic Institute of Natural History
Jóhannsdóttir, A. L. (2021). Íslenskar lækningajurtir: Söfnun þeirra, notkun og áhrif. Reykjavík: Mál og menning
Gladstar, R. (2012). Medicinal Herbs: A Beginner's Guide. North Adams: Storey Publishing
Jónsson, B. L. (1973). Íslenskar lækninga- og drykkjarjurtir. Reykjavík: Náttúrulækningafélag Íslands
Bjarnason, A. (1860). Um íslenskar drykkurtir. Akureyri: H. Helgason
Halldórsson, B. (1781). Grasnytjar. Kaupmannahöfn
Maria Hrefna Hjalmarsdottir Ringdal
