Louisiana Iris

Check out tips on which important factors will help these perennials to thrive.

Plant type: Herbaceous perennial
Hardiness: USDA Zones 4 to 9

Louisiana iris are hybrids of five species, including I. brevicaulis, I. fulva, I. hexagona, I. nelsonii and I. giganticaerulea. Native to southern Louisiana and the Gulf Coast area. The Louisiana iris flower has six petals. Flowers are red, purple, blue, yellow, white and bicolors and have a flattened appearance. Blooms in summer. Foliage is narrow, green and swordlike. Despite the name, Louisiana iris can be grown in northern climates, including North Dakota and the Midwest. Plant size is three to four feet tall and three feet wide.

How to use it: Plant in mass for full effect. Use in the front of a mixed perennial border or near a water feature.

Culture: Prefers a rich, acidic soil with plenty of moisture. If summers are dry, provide supplemental water to encourage blooming or move to a wet site. Never let it dry out. Plant in full sun to partial afternoon shade (in hot climates and desert southwest). Benefits by heavy fertilization. Louisiana iris have rhizomes which are thick, fleshy stems that grow underground. To plant rhizomes, dig a shallow hole just below the soil surface. Place rhizomes with the growing tip pointed up and roots pointed down. Make sure the growing tip is oriented in the direction where you want it to go since the fan will grow from that point. If planting several rhizomes, space approximately one foot apart. Primarily propagated through division. Dig and divide only when plants have less vigorous flowering. Don't let it dry out during transplanting. Can be divided in spring or fall. May have problems with iris borer, slugs or snails.

Special notes: The name iris is derived from Greek mythology where Iris was the goddess of the rainbow, therefore aptly named for its variety of flower colors. Ideal for wet sites. Blooms after bearded and Siberian iris and before Japanese iris. Louisiana iris has the purest form of a red flower of any iris. Attracts wildlife, including bees.

Selected cultivars

  • 'Cajun Sunrise'. Features brilliant red flowers with a yellow sunburst in the center. Tolerates a variety of growing conditions. Reaches about three feet tall.
  • 'Professor' series. Includes 'Professor Barbara' (yellow), 'Professor Ike' (violet) and 'Professor Neil' (burgundy red).
  • 'Red Velvet Elvis'. An ode to the King. Velvety dark red flowers with yellow splotches.

Next Up

Planting and Growing Garden Phlox

Learn how to plant, grow and care for this perennial charmer in your garden.

How to Use Canna Lily in the Garden

Turn up the heat in your garden design by adding tropical canna lily. Its exotic beauty makes every planting sizzle.

Are Mums Perennials?

Learn which mums you can count on to color your landscape for years to come.

How to Plant, Grow and Care for Poppy Flowers

An iconic flower, there are actually several types of poppies. Get expert tips and advice for growing and harvesting them all.

What’s the Difference Between an Annual and a Perennial?

Should you pick annuals or perennials when planting your garden? Here's a rundown on the differences between these two types of plants and the pros and cons of each.

Grow Guide: Why Won't My Azaleas Bloom?

Some reasons why your flowers may not be delivering this spring.

Salvia Plants: Growing and Caring for Ornamental Sage

With over 900 species — annuals and perennials — it's easy to find a variety of low-maintenance salvia for your yard.

What Are Perennials?

Explore the wonderful world of perennials and find options for your garden design.

Planting and Caring for Shasta Daisy

Grow a little bit of nostalgia with Shasta daisy. Learn about new colors and forms of this old-fashioned favorite.

How to Grow Daylilies

With some advance planning, you can have glorious daylilies for spring by planting in the fall with this advice from HGTV gardening experts.

Go Shopping

Spruce up your outdoor space with products handpicked by HGTV editors.

Follow Us Everywhere

Join the party! Don't miss HGTV in your favorite social media feeds.