Achillea

Yarrow
Scientific classification
Kingdom: Plantae Division: Magnoliophyta Class: Magnoliopsida Order: Asterales Family: Asteraceae Genus: Achillea L.
Species
many, see text

Achillea is a genus of flowering plants, commonly referred to as yarrow, that are frequently used in garden borders and beds in ornamental horticulture. These plants typically have frilly, hairy, aromatic leaves and flat clusters of small flowers at the top of the stem. The flowers themselves may be small, but the clusters are usually both large and showy. Achilleas have an unusually long flowering period for temperate perennial plants, and most species also have an attractive architectural form. These traits, along with disease and drought resistance, have been combined in strains domesticated as garden plants. Many of these varieties are commercially cultivated and available in nurseries. Such selections offer a range of color in both foliage and flower, and a variety of forms and heights that all have uses in garden design. Achillea species are versatile plants that have uses in both informal and formal ornamental gardens.

In their wild form, they are native to Europe and temperate areas of Asia. A few grow in North America. Several forms of wild Achillea have been used as medicinal herbs.

The genus was named for the Greek mythological character Achilles. According to the Iliad, Achilles' soldiers used yarrow to treat wounds [1], hence some of its common names such as allheal and bloodwort.

Achillea species are used as food plants by the larvae of some Lepidoptera species - see list of Lepidoptera which feed on Achillea. As an attractant for butterflies, they add yet another dimension to the ornamental garden.

Garden Hybrids

Achilleas are themselves attractive in an ornamental garden, and reliably add the presence of butterflies to flower gardens in temperate regions. This aspect of the plant's effectiveness can be amplified by the addition of other mainstays of butterfly gardening, like buddleia (butterfy bush), salvia species, and ageratum, and by the avoidance of pesticides that are harmful or fatal to the butterflies.

Culture

Achilleas are, as a group, drought resistant plants that require full sun and good drainage in order to thrive.

Named varieties

Hybrid Achilleas are commercially available from nurseries in a variety of colors, heights and foliage types.

Species

• Achillea abrotanoides
• Achillea ageratifolia : Balkan Yarrow, Greek Yarrow
• Achillea ageratum : Sweet Yarrow
• Achillea albicaulis
• Achillea aleppica
• Achillea ambrosiaca
• Achillea armenorum
• Achillea asplenifolia
• Achillea atrata
• Achillea aucheri
• Achillea barbeyana
• Achillea barrelieri
• Achillea biebersteinii
• Achillea brachyphylla
• Achillea bulgarica
• Achillea cartilaginea : Silver Spray Yarrow
• Achillea chrysocoma
• Achillea clavennae : Silvery Yarrow
• Achillea clusiana
• Achillea clypeolata
• Achillea coarctata
• Achillea collina
• Achillea cretica
• Achillea crithmifolia
• Achillea cucullata
• Achillea decolorans = synonym of Achillea ageratum Garden Mace
• Achillea depressa
• Achillea distans : Alps Yarrow
• Achillea erba-rotta : Musk Milfoil
• Achillea falcata
• Achillea filipendulina Fernleaf Yarrow
• Achillea fraasii : Filigree Yarrow
• Achillea fragantissima
• Achillea lewisii
• Achillea goniocephala
• Achillea grandiflora
• Achillea griseovirens
• Achillea gypsicola
• Achillea holosericea
• Achillea horanszkyi
• Achillea huteri
• Achillea kelleri
• Achillea kotschyi
• Achillea lanulosa : White Yarrow
• Achillea ligustica : Ligurian Yarrow
• Achillea lingulata
• Achillea macrophylla : Broad-leaved Yarrow
• Achillea membranacea
• Achillea micrantha
• Achillea millefolium : Milfoil, Yarrow, Allheal, Thousand-leaf, Bloodwort, Carpenter's Grass, Cammock, Green arrow, Gordoloba, Plumajillo, Sneezeweed, Nosebleed, Green Adder's Mouth, Soldier's Woundwort, Dog Daisy, Old-man's-pepper
  • Achillea millefolium alpicola : Common Yarrow
  • Achillea millefolium arenicola : Common Yarrow
  • Achillea millefolium borealis : Boreal Yarrow, Northern Yarrow
  • Achillea millefolium californica : California Yarrow, Western Yarrow
  • Achillea millefolium gigantea : Giant Yarrow
  • Achillea millefolium litoralis : Coast Yarrow
  • Achillea millefolium megacephala : Largehead Yarrow
  • Achillea millefolium millefolium : Common Yarrow
  • Achillea millefolium nigrescens : Common Yarrow
  • Achillea millefolium occidentalis : Western Yarrow
  • Achillea millefolium pacifica : Pacific Yarrow
  • Achillea millefolium puberula : Common Yarrow
• Achillea mongolica = synonym of Achillea sibirica
• Achillea monocephala
• Achillea moschata : Musk Milfoil, Forest Lady's Herb
• Achillea nana : Dwarf Alpine Yarrow
• Achillea nobilis : Noble Yarrow, Creamy Yarrow
• Achillea ochroleuca
• Achillea odorata
• Achillea oxyloba
• Achillea oxyodonta
• Achillea pannonica
• Achillea phrygia
• Achillea ptarmica : Sneezewort, Sneezeweed, Seezewort Yarrow, Bachelor's Buttons
• Achillea pyrenaica
• Achillea roseo-alba
• Achillea rupestris
• Achillea santolina
• Achillea schischkinii
• Achillea sedelmeyeriana
• Achillea setacea
• Achillea sibirica : Siberian Yarrow
• Achillea sintenisii
• Achillea sipikorensis
• Achillea sudetica = synonym of Achillea millefolium alpestris
• Achillea sulpherea
• Achillea talagonica
• Achillea taygetea
• Achillea tenuifolia = synonym of Achillea millefolium millefolium
• Achillea tomentosa : Woolly Yarrow
• Achillea tzsonii
• Achillea umbellata
• Achillea vermicularis
• Achillea vermiculata
• Achillea virescens
• Achillea wilhelmsii
• Achillea wilsoniana : Wilson's Yarrow

References

• Why was yarrow named for Achilles? (killerplants.com)