The species has a long history of use in traditional medicine in its native range, where it is employed as a treatment for a variety of ailments. This has led to the investigation of its phytochemistry. Its flowers can be eaten in salads or crushed for dyemaking, and the plant has been considered for potential use in the phytoremediation of contaminated soil
Description
Perovskia atriplicifolia is a deciduous perennial subshrub with an erect to spreading habit.[13][27] Superficially, it resembles a much larger version of lavender.[28] Multiple branches arise from a shared rootstalk,[8] growing to a height of 0.5–1.2 m (1 ft 8 in–3 ft 11 in),[8][22] with occasional specimens reaching 1.5 m (4 ft 11 in).[4] The mature plant may be 0.6–1.2 m (2 ft 0 in–3 ft 11 in) across.[4] The rigid stems are square in cross-section,[4] and are covered by a indumentum formed by stellate, or star-shaped, trichomes and oil droplets.[27] Especially during autumn, these hairs give the stems a silvery appearance.[29]
The grayish-green leaves are arranged in opposite pairs,[13][30] and attached to the stems by a short petiole.[27] They are generally 3–5 cm (1.2–2.0 in) long and 0.8–2 cm (0.3–0.8 in) wide,[27] although narrower in some populations.[8] The overallleaf shape is oblate, a rounded shape longer than it is wide, to lanceolate, shaped like the head of a lance.[27] They arepinnatipartite,[8] with a deeply incised leaf margin that may be either wavy or sharp-toothed; even within a single community of P. atriplicifolia, there can be considerable variation in the details of leaf shape.[27] Leaves near the top of branches may merge into bracts.[27] The foliage is aromatic, especially when crushed,[4] with a fragrance described as sage-like,[5] a blend of sage and lavender,[16] or like turpentine.[31]
The flowering season of P. atriplicifolia can be as long as June through October,[27] although populations in some parts of its range, such as China, may bloom in a much more restricted period.[8] The inflorescence is a showy panicle, 30–38 cm (12–15 in) long,[4] with many branches.[32] Each of these branches is a raceme, with the individual flowers arranged in pairs called verticillasters.[8] Each flower's calyx is purple, densely covered in white or purple hairs, and about 4 mm long. Thecorolla is tube-shaped, formed from a four-lobed upper lip and a slightly shorter lower lip; the blue or violet blue petals are about 1 cm long.[8][32] The style has been reported in both an exserted—extending beyond the flower's tube—form and one contained within the flower;[32] all known examples of P. atriplicifolia in cultivation have exserted styles.[13] Gardening author Neil Soderstrom describes the appearance of the flowers from a distance as "like a fine haze or fog".[33]
Fruits develop about a month after flowering,[8] and consist of dark brown oval nutlets, about 2 mm × 1 mm.
