This plant is a small deciduous tree or multi-stemmed shrub that can reach heights of up to 18 feet but is typically seen as an 8-foot shrub. It blooms continuously on new growth from spring through winter, with peak flowering occurring in summer. The tiny 2-inch long dark red flowers are on long 2-foot terminal racemes arch out and above the foliage on 6-foot long stems. After flowering, trimming back and pruning hard in winter to maintain its shape is recommended. This plant inherits hardiness from its parentage (a cross between E. herbacea and E. crista-Galli), making it hardy to 20°F without damage and root hardy below this temperature. It is suitable for USDA Zones 7b to 10b, which is unusual for a Coral Tree. This excellent garden plant is one of the best and most diminutive coral trees. Over time and with some training, it can develop into a lovely miniature tree despite being typically seen as a shrub.

This plant resulted from a cross between Erythrina herbacea, a North American species, and Erythrina crista-Galli from South America. William MacArthur first created this hybrid in the early 1840s at Camden Park in Australia. MacArthur was one of Australia's most active and influential horticulturists and was initially named the plant Erythrina Camden. Later, while living in Sydney, the English botanist John Carne Bidwill sent a plant to the botanist William Herbert in England. He suggested that the plant be named Erythrina MacArthur in honor of its originator.