By Nikki Phipps
With its unusual flowers, attractive shape and ease of cultivation, the African iris plant is fairly versatile in the garden. This African native (Dietes bicolor) grows from rhizomes that produce clumps of slender, arching leaves with flat, creamy-white flowers and black markings which last only one day. Although its flowers are short lived, they are numerous with each 2- to 4-foot-tall stalk producing a mass of buds that bloom continuously from spring throughout late summer.
African Iris Plant Info
Dietes is only found in South Africa and on Lord Howe Island between Australia and New Zealand. There are six species of Dietes, five from tropical Africa and one from Lord Howe Island.
The genus name “Dietes” is derived from the Greek “dis” which means twice and “etes” which means an associate—twice – pertaining to its position between Moraea and Iris, two of its relatives. They were previously classified in the genus Moraea, but members of that genus are not rhizomatous. Since the African iris was formerly classified in this genus, it is still at times referred to as Morea iris by some gardeners. The species name “bicolor” means two-colored. Other Dietes species include the Fortnight lily and Butterfly iris.
The African iris plant is fast growing, making it ideal for use in areas that need to be established quickly. Its evergreen foliage and spreading habit makes African iris suitable for use as a long-lasting and dramatic ground cover. It is often grown in mixed beds and borders because the narrow leaves provide a strong vertical element. African irises also look excellent planted along foundations. Additionally, the large spiky clumps of African iris make it ideal for use as an accent plant near ponds or at the sides of steps, pathways and entrances.
How to Grow an African Iris
In the garden, growing African Dietes irises thrive in Mediterranean-like climates, 8b and higher. While preferring areas of full sun, locations having light, dappled shade can be used as well. Plant the rhizomes of this spectacular flower any time of the year about an inch or so deep in well-drained soil.
Once established, African iris care is easy, and the plant will tolerate poor soil conditions. Although occurring naturally near streams and in marshy places, it is also drought resistant and frost hardy.
African iris generally blooms more regularly with continual water; therefore, regular watering should be performed throughout its growing season, reducing as flowering lessens. Keep growing African Dietes irises dry during winter and protect them with a layer of mulch, especially in colder regions.
Because the African iris multiplies rapidly, it can be easily propagated by dividing the clumps in the fall. The new divisions may take several weeks to get established. They can also be grown from seed and, under ideal growing conditions, may even seed themselves. The seed capsules of the African iris, shaped liked little footballs, can be collected and used to sew new plants the following season.