Boronia is a genus made up of about 95 evergreen shrubs, all of which are native to Australia, except one that is endemic to Tasmania. Found in forests and woodlands, Boronia species have perfumed flowers that grow in bell or cup shapes and in colors of pink, maroon and yellow. In addition to the smell of its flowers, the deep green leaves of the shrub produce an aromatic fragrance when crushed.
The flowers have four to five petals and an equal number of stamens to petals or twice the number of stamens to petals, depending on the species. In Australia, Boronia species start to flower in July and continue through early December. The flowers cluster on the stems of the shrub and are attractive to bees, butterflies and birds. Beetles and moths pollinate the flowers, and ants are thought to be primarily responsible for the dispersal of the shrub’s seed.
The Boronia genus is a member of the Rutaceae family, which includes citrus trees. Unlike most of its family members, Boronia species produce wiry stems and needlelike leaves. Some species can grow to 6 feet (1.8 m) in height, but most species of Boronia are small to medium-sized shrubs.
Brown boronia, Boronia megastigma, is harvested for the production of essential oils and red boronia, Boronia heterophylla, is harvested for cut flowers. The essential oils are used in perfumes, cosmetics and food coloring. Claims also have been made that the essential oil has healing properties that include helping the user to feel calmer, to end obsessive thoughts and to deal with relationships.
Some species of Boronia are at risk because of habitat loss and overuse as a food source by feral pigs and goats. One species is thought to be extinct. New species, however, have been discovered, but these species have only limited numbers of individual plants and have very limited distribution.
Cultivation of Boronia has proven difficult but is now being done with the species Berberis heterophylla and Boronia megastigma in Australia and New Zealand. Boronia is most easily cultivated in well-drained soils with a slightly acidic potenz hydrogen (pH) factor. Rooted cuttings are planted in the spring, and both young and mature plants need a windbreak.
The Boronia species will do best with filtered light. If successfully cultivated, species of this genes flower within a year to 15 months after planting. The plants typically survive five to eight years.