Many of the plants in the Doronicum genus of the Asteraceae family go by the common name of leopard's bane. Generally, growers cultivate these deciduous perennials for their showy, yellow blooms that usually come in early spring. There are about 35 species and a multitude of cultivars in the Doronicum genus, giving gardeners a large variety from which to choose. The flowers are composite flowers, similar to daisies and brachyglottis blooms. In their native regions in parts of Europe, Siberia, and Asia, they grow in woodland edges, meadows, and rocky areas.
Most gardeners plant Doronicum plants as garden borders or in perennial beds and as cut flowers. The plants usually thrive in areas of dappled shade or partial shade in temperate climates, but most will grow in full sun. Most of the species might self-seed, thereby posing a risk of invading a garden or surrounding areas. Growers propagate them by sowing seeds or by dividing established plants.
The Doronicum flowers are composite flowers, meaning that each flowerhead contains two types of flowers — ray and disk florets. The ray florets are the outer petals of the flowerhead; the disk florets are the inner flower. The ray florets are strap-shaped, bright yellow attention getters. They draw the insects to the flowerhead, but are sterile and do not produce seeds. The tiny disk flowers usually are a darker yellow, resembling small, domed buttons in the flowerhead's center.
Some botanists advise that Doronicum plants are generally poisonous, but in past centuries herbalists used it as a remedy for scorpion and snake bites. In other areas, people used preparations to treat depression and melancholy, as well as to tone the heart muscle. The plant contains pyrrolizidine alkaloids and may cause liver and lung damage. Often chemicals released by crushing the leaves and flowers may cause sneezing.
One of the most popular species is D. orientale, which nurseries often label as D. caucasicum. Typically it is 2 feet (about 61 cm) tall and up to 36 inches (91 cm) across. It is native to southeastern Europe, parts of Lebanon, and Turkey, but may be invasive in domestic gardens. Some cultivars of this species have double flowers, where the extra ray florets cover the disk florets.
The size of Doronicum plants depend largely on the species and cultivar. D. plantagineum, another popular species, grows to heights of 5 foot (1.5 m), with large flowers that may range between 2 to 4 inches (about 5 to 10 cm) across. In contrast, D. cordifolium is an alpine species that may reach heights of 5 inches (about 13 cm). It is a rock garden favorite of many gardeners.