Alyogyne is a genus of xerophytic shrubs made up of four species that formerly were classified as part of the hibiscus genus. The shrubs have many branches and are covered in stellate hairs. They grow in the sandy to gravely areas of southern and western Australia. Producing an abundance of flowers each season, the alyogyne species are differentiated from the hibiscus species by having an undivided style. The genus is part of the malvaceae family.
The blue hibiscus, which has the scientific name of Alyogyne huegelii, and the red-centered hibiscus, Alyogyne hakeifolia, have been cultivated for use as decorative shrubbery. The blue hibiscus grows to about 8 feet (2.5 m) in height and has leaves that are up to 3 inches (7 cm) in length. The leaves are bright green and lobed in three to five segments. Producing hundreds of flowers, the blooms are 3 to 4 inches (7 to 10 cm) and come in colors of yellow, white, lilac, pink and mauve.
The red-centered hibiscus grows to heights of about 10 feet (3 m) and has leaves that are dark green and similar in appearance to needles. Blooms are 1 to 2.5 inches (5 to 6 cm) long and are tubular-shaped. Coming in colors of mauve, yellow and pink, they have a dark red center.
Alyogyne pinoniana, the sand hibiscus, can be as small as 3 feet (1 m) but can grow to nearly 10 feet (3 m) and is a sprawling shrub. It flowers between late winter and early summer with blooms of blue, lilac and mauve. The flowers are as much as 3.5 inches (9 cm) across.
The coastal hibiscus, Alyogyne cuneiformis, is small to medium-size and produces tubular-shaped flowers that are more than 2 inches (6 cm) long. The flowers are white and have a dark red center. Not widely cultivated, the coastal hibiscus has been grown in greenhouses.
When cultivated, plants of the alyogyne species are susceptible to scale insects, aphids and red spider mites. Some hybrids have developed naturally, and some have been cultivated. Alyogyne bushes grow fast and need to be pruned regularly. The shrubs should be planted in locations with good soil drainage, full sun and some protection from the wind.
Alyogyne also can be grown as a potted plant. Propagation is most successful from seed or cutting. While somewhat tolerant of frost, alyogyne species cannot survive temperatures colder than 25 degrees Fahrenheit (minus-3.8 Celsius).