Spanish broom, also known as the weaver’s broom, is a perennial plant indigenous to the Mediterranean region and some parts of Africa and Asia. It bears the scientific name Spartium junceum, synonymous with Genistia juncea. After its introduction as an ornamental plant in San Francisco of the United States in 1858, it became widely distributed in surrounding areas. This deciduous plant normally grows from 6 to 10 feet (2 to 3 m) tall with dense stems. These stems are bright green, smooth, and hairless.
This plant is almost leafless, though the existing leaves are less than 1 inch (2.5 cm) long, lance-shaped, and short-lived. The flowers of the Spanish broom plant are about 1 inch (2.5 cm) long, pea-shaped, and bright yellow. They begin blooming in July and grow in clusters at the ends of branches on stalks. This evergreen shrub has a deep-branched tapering root called a taproot, resulting in the plant being difficult to uproot.
In the wild, Spanish broom grows on dry, stony, and limestone soils without need for much watering. It is tolerant of urban pollutants, coastal winds that contain salt, and temperatures as cool as 14 ºF (-10 ºC). This plant needs full sunlight for optimal growth and, although it is typically intolerant of heavy shade, it can grow in areas where there is minimal shade.
The reproduction of Spanish broom is usually done through its seed. When the pods dry upon maturity, they burst open into halves and eject the seeds a short distance from the plant. These seeds usually germinate without being cared for, but scraping the seed’s outer covering can encourage germination. Without any intervention, the seeds are widely dispersed by both water and soil movement. Animal and human activities, as well as the use of vehicles and machinery, can also play a part in their dispersal.
In its natural habitat, the stems and fibers of Spanish broom are used to make paper, ropes, and baskets. The flowers are processed to produce a yellow coloring dye. An essential oil used in perfumery can also be extracted from the flowers. This plant is widely used as an ornamental garden plant and as bank covers in rocky soil.
Spanish broom is a highly invasive plant due to its prolific seed production and aggressive encroachment on available land. Desirable natural vegetation is crowded out as a result. In the California region of the United States, for example, Spanish broom is considered a fire hazard. Ways of controlling its growth include disturbing of the soil where it is planted and manually pulling young plants.