NURTURE
DANGERS OF AND ALTERNATIVES TO THE DUTCH IRIS
AlterNATIVE choices
LOUISIANA IRIS Invasive plant
IRIS PSEUDACORUS FLOWER, DUTCH IRIS
Benefits The series Hexagona holds the five species of Louisiana Iris, so named for the unique six-sided seed capsule and their greatest profusion in Louisiana. New Orleans was once called the “Iris Capital of the World.” These are perennial, rhizomatous iris with no midrib in the leaf. Most species grow from Texas to North Carolina, up the Mississippi River valley to Ohio and Indiana. Water is essential for their growth and distribution. Today, destruction of natural wet areas and invasive species are the foremost threats to wild populations. There are many hybrids and variants with differing garden characteristics based on the five parent plant species. All are dormant in summer, start growth in fall and bloom in spring. Rhizomes need dividing every 2–3 years. The vibrant clumps of upright green leaves enliven the gray winter landscape.
IRIS BREVICAULIS, ZIG-ZAG IRIS • This invasive species, native to Europe and west Asia, has been planted as an ornamnetal due to its showy yellow blooms and dense green stands in the summer. • I t is easily identified by its large yellow flowers and prominent raised midrib on the leaf. • This iris grows quickly to form dense, monotypic stands that reduce diversity and can alter waterways. • The roots and leaves are poisonous, both to wildlife and livestock. It is a Tier 1 invasive species in Louisiana deemed as “currently having severe or widespread negative impacts on wildlife or natural communities in Louisiana.” It is now found throughout the U.S.
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Pro Landscaper USA South May/June 2022
• This is the shortest (both in leaf and stalk) iris in the Louisiana series. The stalk is erect to sprawling, 10-14", and has a distinct zig-zag form. • The large showy flowers with dark veining can have the deepest blue of all; blooms are below foliage height. • The most widely distributed Louisiana iris, found on wet sites from prairies to marshes to bottomlands, with the greatest adaptation to cold and more upland areas.
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