The fall rains have arrived. You can almost hear the Louisiana irises rejoicing. Iris giganticaerulea is the official state wildflower of Louisiana, but Louisiana irises also grow well in East Texas.
Although you can grow Louisiana irises as a bog plant, they also grow well in regularly irrigated garden conditions, even tolerating drought to an extent. They tend to go dormant during the dry season, growing again when the autumn rains return.
Louisiana irises form large patches, with rhizomes that can grow up to eight inches in one season. It is often recommended that your Louisiana irises be fertilized twice a year – in the fall and spring – and that their large seedpods be removed. Because of their rapid growth, the hardest part of growing Louisiana irises may be finding where to put additional plants from the necessary thinning.
Louisianans: Five Species of Irises
Although it is possible to acquire the species plants, most of the Louisiana irises found in gardens are a hybrid of five different species of irises. These five species grow in various parts of the United States, but are only found growing together naturally in southern Louisiana. Because these five species are closely related, they have been crossed to form cultivars of various colors ranging from blue, red, white and yellow.
These five species are known collectively as the “Louisianans”. Iris brevicaulis is known as the zigzag iris, with a native range from Nebraska to Texas. Naturally blue to bright purple, it gets its common name from its zigzag stem. Iris fulva is known as the copper iris. It has a large native range, from Illinois to Texas, and comes in stunning colors of red.
Iris giganticaerulea is the largest of the five irises, with a native range from Mississippi to Texas. Its blooms are usually blue or purple. Iris hexagona is not native to Texas, with a native range from Alabama to South Carolina, including Florida. It comes in white, pink, and purple. Iris nelsonii’s native range only includes Louisiana. It blooms red, copper or bright purple.
There are various other qualities separating each of those five iris species including the signal, the sepals, petals and stalks. However, for the standard East Texas gardener, all you need to know is that Louisiana irises are easy to grow, should multiply well, and bloom in spring at the same time as the roses.
Certified as a landscape design consultant, Lydia Holley is past President of Henderson County Master Gardener Association. Lydia lives on land that has been in her family for five generations, and like many gardeners, she tries to grow one of everything. A member of East Texas Writers Guild, Lydia’s short story, Three Dreams and An Angel, will be published this fall.