From The Plant Encyclopedia
1 - 12
- Cultivation: Naturalizing, Low-Maintenance, For-Gardeners
- Light: Sun
- Soil: Mid-Fertility, Poor, Loam, Clay, Sand, Rock
- pH: 5, 6, 7
- Moisture: Medium, Dry, Well-Drained
- Form: Herbaceous
- Habit: Perennial
- Flower: Large, Floret, Yellow, Orange, Red, Pink, Purple, Silver, White
- Fruit/Seed: Small, Seed, Black
- Foliage: Leaves, Green, Silver
- Uses: Edible, Medicinal, Ornamental
Achillea (pronounced /ækɨˈliːə/)<ref>Sunset Western Garden Book, 1995:606–607</ref> is a genus of about 85 flowering plants, in the family Asteraceae, commonly referred to as yarrow. They occur in Europe and temperate areas of Asia. A few grow in North America. These plants typically have frilly, hairy, aromatic leaves.
These plants show large, flat clusters of small Flowers at the top of the stem. These flowers can be white, yellow, orange, pink or red. A number of species are popular garden plants.
Achillea or yarrow is native to the Northern Hemisphere. In New Mexico and southern Colorado, it is called plumajillo, or "little feather", for the shape of the leaves. In antiquity, yarrow was known as herbal militaris, for its use in staunching the flow of blood from wounds. Other common names for this species include common yarrow, gordaldo, nosebleed plant, old man's pepper, devil's nettle, sanguinary, milfoil, soldier's woundwort, thousand-leaf (as its binomial name affirms), and thousand-seal.
Common yarrow is an erect herbaceous perennial plant that produces one to several stems (0.2 to 1m tall) and has a rhizomatous growth form. Leaves are evenly distributed along the stem, with the leaves near the middle and bottom of the stem being the largest. The leaves have varying degrees of hairiness (pubescence). The leaves are 5–20 cm long, bipinnate or tripinnate, almost feathery, and arranged spirally on the stems. The leaves are cauline and more or less clasping. The inflorescence has 4 to 9 phyllaries and contains ray and disk flowers which are white to pink. There are generally 3 to 8 ray flowers that are ovate to round. Disk flowers range from 15 to 40. The inflorescence is produced in a flat-topped cluster. Yarrow grows up to 3500m above sea level. The plant commonly flowers from May through June, and is a frequent component in butterfly gardens. Common yarrow is frequently found in the mildly disturbed soil of grasslands and open forests. Active growth occurs in the spring.
Popular Cultivated Species
Meadow Yarrow Achillea millefolium
Wooly Yarrow Achillea filipendulina
Cultivation and uses
Yarrow flowers, late summer, Yosemite National Park.
Yarrows can be planted to combat soil erosion due to the plant's resistance to drought.
The herb is purported to be a diaphoretic, astringent, tonic, stimulant and mild aromatic. It contains isovaleric acid, salicylic acid, asparagin, sterols, flavonoids, bitters, tannins, and coumarins. The plant also has a long history as a powerful 'healing herb' used topically for wounds, cuts and abrasions. The genus name Achillea is derived from mythical Greek character, Achilles, who reportedly carried it with his army to treat battle wounds. This medicinal action is also reflected in some of the common names mentioned below, such as Staunchweed and Soldier's Woundwort.
The stalks of yarrow are dried and used as a randomising agent in I Ching divination.
In the Middle Ages, yarrow was part of a herbal mixture known as gruit used in the flavouring of beer prior to the use of hops.
Old folk names for yarrow include arrowroot, bad man's plaything, carpenter's weed, death flower, devil's nettle, eerie, field hops, gearwe, hundred leaved grass, knight's milefoil, knyghten, milefolium, milfoil, millefoil, noble yarrow, nosebleed, old man's mustard, old man's pepper, sanguinary, seven year's love, snake's grass, soldier, soldier's woundwort, stanch weed, thousand seal, woundwort, yarroway, yerw.
The English name yarrow comes from the Saxon (Old English) word gearwe, which is related to both the Dutch word gerw and the Old High German word garawa.
Yarrow has also been used as a food, and was very popular as a vegetable in the seventeenth century. The younger leaves are said to be a pleasant leaf vegetable when cooked as spinach, or in a soup. Yarrow is sweet with a slight bitter taste. The leaves can also be dried and used as a herb in cooking.
Agricultural Use: before the arrival of monocultures of Ryegrass, both grass leys and permanent pasture always contained Yarrow (Achillea millefolium) at a rate of ca. 0.3 kg/ha. At least one of the reasons for Yarrow's inclusion in grass mixtures was that it is a deep rooted herb, whose leaves are rich in minerals. Thus its inclusion helped to prevent mineral deficiencies in the ruminants to whom it was fed.
Yarrow has seen historical use as a medicine, often because of its astringent effects. Decoctions have been used to treat inflammations, such as hemorrhoids, and headaches. Confusingly, it has been said to both stop bleeding and promote it. Infusions of yarrow, taken either internally or externally, are said[by whom?] to speed recovery from severe bruising. The most medicinally active part of the plant is the flowering tops. They also have a mild stimulant effect, and have been used as a snuff. Today, yarrow is valued mainly for its action[clarification needed] in colds and influenza, and also for its effect on the circulatory, digestive, excretory, and urinary systems. In the nineteenth century, yarrow was said to have a greater number of indications than any other herb.
It is believed[by whom?] that anti-allergenic compounds can be extracted from the flowers by steam distillation. The flowers are used to treat various allergic mucus problems, including hay fever. Flowers used in this way are harvested in summer or autumn, and an infusion drunk for upper respiratory phlegm or used externally as a wash for eczema. Inhale for hay fever and mild asthma, use fresh in boiling water.
The dark blue essential oil, extracted by steam distillation of the flowers, is generally used as an anti-inflammatory or in chest rubs for colds and influenza. For a massage oil for inflamed joints, dilute 5-10 drops yarrow oil in 25 ml infused St. John's wort oil. A chest rub can be made for chesty colds and influenza. Combine yarrow with eucalyptus, peppermint, hyssop, or thyme oil, diluting a total of 20 drops of oil in 25 ml almond or sunflower oil.
The leaves encourage clotting, so it can be used fresh for nosebleeds. However, inserting a leaf in the nostril may also start a nosebleed; this was once done to relieve migraines. Harvest throughout the growing season.
The aerial parts of the plant are used for phlegm conditions, as a bitter digestive tonic to encourage bile flow, and as a diuretic. The aerial parts act as a tonic for the blood, stimulate the circulation, and can be used for high blood pressure. Also useful in menstrual disorders, and as an effective sweating remedy to bring down fevers. Harvest during flowering. The tincture is used for urinary disorders or menstrual problems. Prescribed for cardiovascular complaints. Soak a pad in an infusion or dilute tincture to soothe varicose veins.
Yarrow intensifies the medicinal action of other herbs taken with it, and helps eliminate toxins from the body. It is reported to be associated with the treatment of the following ailments:
Analgesic Amenorrhea, antiphlogistic, anti-inflammatory, bowels, bleeding, blood clots, blood pressure (lowers), blood purifier, blood vessels (tones), catarrh (acute, repertory), colds, chicken pox, circulation, contraceptive (unproven), cystitis, diabetes treatment, digestion (stimulates)gastro-intestinal disorders, choleretic  dyspepsia, eczema, fevers, flu, gastritis, glandular system, gum ailments, heartbeat (slow), influenza, insect repellant, inflammation, emmenagogue, internal bleeding, liver (stimulates and regulates), lungs (hemorrhage), measles, menses (suppressed), menorrhagia, menstruation (regulates, relieves pain), nipples (soreness), nosebleeds, piles (bleeding), smallpox, stomach sickness, toothache, thrombosis, ulcers, urinary antiseptic, uterus (tighten and contract),gastroprotective  varicose veins, vision, may reduce autoimmune responses.
The salicylic acid derivatives are a component of aspirin, which may account for its use in treating fevers and reducing pain. Yarrow tea is also said to be able to clear up a cold within 24 hours. Yarrow has also been used as a Quinine substitute.
Yarrow was also used in traditional Native American herbal medicine. Navajo Indians considered it to be a "life medicine", chewed it for toothaches, and poured an infusion into ears for earaches. Several tribes of the Plains region of the United States used common yarrow. The Pawnee used the stalk for pain relief. The Chippewa used the leaves for headaches by inhaling it in a steam. They also chewed the roots and applied the saliva to their appendages as a stimulant. The Cherokee drank a tea of common yarrow to reduce fever and aid in restful sleep.
Yarrow is considered an especially useful companion plant, not only repelling some bad insects while attracting good, predatory ones, but also improving soil quality. It attracts predatory wasps, which drink the nectar and then use insect pests as food for their larvae. Similarly, it attracts ladybugs and hoverflies. Its leaves are thought to be good fertilizer, and a beneficial additive for compost.
It is also considered directly beneficial to other plants, improving the health of sick plants when grown near them.