About Eremophila glabra (R.Br.) Ostenf.
Eremophila glabra (R.Br.) Ostenf. is a shrub that grows between 0.1 and 3 meters (0.3 to 10 feet) in height, and can be either prostrate or erect. Its leaves are arranged alternately along stems, and may be crowded or sparse. Leaves are most commonly lance-shaped, but can also be linear or egg-shaped, measuring 7.5 to 61 millimeters (0.3 to 2 inches) long and 0.8 to 18 millimeters (0.03 to 0.7 inches) wide. Leaf tips are pointed, and leaf bases taper gradually toward the stem. Both leaves and stems are covered with small, raised glands. Flowers grow singly or in pairs in leaf axils, on stalks 3 to 10 millimeters (0.1 to 0.4 inches) long. They may be red, orange, yellow, or yellowish green, and do not have spots. There are 5 sepals that range from narrow egg-shaped to triangular, and differ slightly in length. The colored petals measure 20 to 30 millimeters (0.8 to 1 inch) long, and are joined into a tube ending in 5 lobes. The upper two lobes are pointed and usually close together, while the lower lip is blunt and curves backwards. Four stamens extend past the end of the petals. Flowering occurs between early autumn and summer, which corresponds to March to December in Australia, and is followed by fruit. Fruits are oval to nearly spherical, around 4 to 9 millimeters (0.2 to 0.4 inches) in diameter, hairless, and can be dry or fleshy, and dark brown. This eremophila species is found across all mainland states of Australia. Subspecies glabra is the most widely distributed, growing in a wide range of soils and vegetation associations, but only occurs in the continent's drier areas. Common name tar bush, this species is one of the most variable in the genus Eremophila; using multiple different forms in a single garden can give the impression of many distinct species. Most forms require little maintenance beyond occasional watering and light pruning. Propagating this species from seed is difficult, but cuttings root easily and retain the characteristics of the parent plant. Eremophila glabra grows well in most soils and positions, ranging from full sun to full shade. Most forms are drought tolerant and survive most frosts, though a few forms with hairy leaves cannot tolerate high humidity. It is popular in native Australian gardens, and several cultivars have been developed. Two commercially available cultivars are the yellow-flowered prostrate form 'Kalbarri Carpet', and 'Murchison Magic', a silvery-leaved form with red flowers.
