Horticulture/Artemisia vulgaris

Artemisia vulgaris (Mugwort) is a species in the family ../Asteraceae/. It is one of several species in the genus Artemisia/ known as mugwort, and is also occasionally known as Felon Herb, St. John's Plant, Chrysanthemum Weed, and Wild Wormwood. It is native to temperate Europe, Asia and northern Africa, but is also present in North America as an invasive weed. It is a very common plant on nitrogenous soils such as waste places and roadsides.

Description
It is a tall herbaceous perennial plant growing 1–2 m (rarely 2.5 m) tall, with a woody root. The leaves are 5–20 cm long, dark green, pinnate, with dense white tomentose hairs on the underside. The erect stem often has a red-purplish tinge.

The rather small flowers (5 mm long) are radially symmetrical with many yellow or dark red petals. The narrow and numerous capitula (flower heads) spread out in racemose panicles. It flowers from July to September.

Similar species
A. vulgaris is often confused with the Chinese mugwort (A. verlotiorum), which is very common too. The latter has oblonge reddish to brown capitula, its stems are green and the leaves broader, lighter coloured and more dense on the stem. The plant's scent is both stronger and more pleasant than that of the common mugwort. It flowers very late in the summer, but reproduces mainly by stolons, thus forming thick groups. The two species share the same habitats.

Mugwort is also sometimes confused with the ragweeds. In the garden, the foliage can look similar to that of hardy mums (Dendranthema spp.), but can be distinguished easily by the light-colored undersides of the leaves, as opposed to the green undersides of chrysanthemum leaves.

Uses
Mugwort has both culinary and herbal uses. See the Wikipedia article on Artemisia vulgaris for details.

Control
This plant is very aggressive in the garden, and can be very difficult to eradicate once established.