On Gardening: Louisiana irises offer gracefulness and elegance for gardens everywhere

April 25, 2016

Jeri offers gardeners what many consider to be one of the most intense blue colors in the world of flowers

Recently the Coastal Georgia Botanical Gardens in Savannah, Ga., has been building bridges, though they might look short, in reality they stretch all the way to Louisiana.

Thanks to almost a thousand rhizomes courtesy of a leading Louisiana iris nursery, we are now showing thousands of visitors, and a region of the country, the incredible display potential of the Louisiana iris. The new bridges mentioned above actually serve as special vista points overlooking the incredible array of color in our winding bog.

Although I say bog and though Louisiana irises are native to swamps, and perform well in actual water gardens, the typical fertile garden soil of your home may prove to be just perfect for a show like you have never experienced.

Taxonomical descriptions or identifications if you will, of Louisiana irises prove to be more challenging than actually growing the plant. Instead of me giving a treatise on their nomenclature I turned to my good friends Dan Gill and Allen Owings, extension horticulturists with Louisiana State University which is after all ground zero for Louisiana iris.

They describe five species of being ‘The Louisianans.’ These are Iris brevicaulis, Iris fulva, Iris giganticaerulea, Iris hexagona and Iris nelsonii. According to Gill and Owings, Iris brevicaulis and I. fulva are native along the Mississippi north to Ohio but only in Louisiana are all five found. They are all closely related and will interbreed with each other but no other species.

If you have never paid attention to Louisiana irises, then you will most likely be in for a shock. It will most likely thrill you to see all of the new selections, colors and color combinations. In looking at ours it seems as every color in the rainbow is there including those with multi-colors and ruffles. The best of all is that these incredible flowers are borne on plants that might be best described as graceful if not exquisite.

If your interest is starting to peak, then know that Louisiana irises can be grown from zones 6-10. They perform best with at least 6 hours of direct sunlight per day. The soil should be fertile and organically rich. If your soil is sandy then amend with 3 to 4 inches of organic matter like compost or humus and incorporate to a depth of 6 to 8 inches. This organic matter will improve condition for those of you with heavy clay.

Rhizomes are best planted in the fall setting just below the soil surface. But if you are like most gardeners you will find them available at the garden center in the spring, growing in containers. These can be planted with great success too, just plant at the same depth as in the container. These are vigorous plants so plan on spacing at least 2 feet apart.

Plants start blooming in March and last into May depending on varieties and regions and then go dormant in the summer. Remove yellowed and unattractive foliage. Plants grown with a lot of moisture available tend to keep more green leaves but regardless expect a flush of growth in the fall. Feed your plants with all-purpose slow release fertilizer in fall and late winter.

The Louisiana iris complements the water garden, ponds and creek beds whether they are dry or flowing. I love them combined with plants like elephant ears, ferns, gingers and King Tut papyrus. Place some in grandma’s cottage garden however and they will look at home and command attention.

If you haven’t looked at Louisiana irises lately it is time to do so. You will fall in love and want as many as you can get to add that special sizzle to your spring garden.



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