Growing Louisiana irises - Part I

Louisiana (LA) irises are part of the "rhizome" sub-division of the species iris.  They are further divided into the sub-division "beardless" irises.  Bearded irises such as the "Tall Bearded" irises are grown throughout the US but do not grow well in the heat of some southern states such as LA, MS and FL, while LA irises flourish in the heat and also will grow in colder climates.

'Honey Star' by J. Hutchinson (1991) from Australia

'Honey Star' has just bloomed in our gardens.  We are having a really early spring this year and the LA irises are starting to pop out everywhere.  LA irises have a bloom season lasting about one and a half months here in northwest LA.  Some irises bloom early, some bloom in the mid season, and some bloom late.  By selecting the irises you want to grow by season as well as beauty, you can have an extended bloom period in your garden. Bloom season starts, usually, in early April and continues into mid May in NW LA.  Bloom season for LA irises in Rochester, NY, is in June or July.

We have already talked about the different ways you can grow LA irises so now we will spend some time on how to plant them.  LA irises should be moved in the fall.  We want them planted after the hot summer is over and before the first frost.  I like to plant them so that they are well established before the real cold starts.  You will have to consider the climate in your area and order your irises to arrive at the appropriate time. When you order LA irises from a supplier they will arrive by mail or other delivery methods and will be trimmed, the rhizome (root part of the plant) will be wrapped in wet paper, and the name of the iris will be either written on the foliage of the iris or on a tag attached to the iris. Unlike tall bearded irises, the rhizome of the LA irises must not be allowed to dry out in shipping.  I suggest you unpack your iris shipment and then remove all the packing materials.  Find an appropriate size container and fill it with about five inches of water.  Then place the LA irises in the contained so the rhizomes are covered with water and the foliage is above water.  The foliage should have already been cut back to 6-8 inches.  If not, now is a good time to do that.  Let the irises set in the water for a couple of days while you finish the preparation of your beds or pots.

LA iris rhizome ready to be planted with clump of  'Clyde Redmond' by Charles Arny (1970) in background

LA irises should be planted one to one and a half inches above the top of the rhizome. The rhizome should never be exposed to the sun. If the LA iris rhizomes start to grow up above the soil, it is time to dig them up, divide them, give some to your neighbors, and replant. Once I have planted the rhizome I give it a good watering and then try to just keep the soil moist, not too wet, until the foliage starts to grow out where it was cut for shipment.

Now that we have the iris planted, we can sit back and watch it grow!

'Creole Rhapsody' by Joe Mertzweiller (1998)

 'Creole Rhapsody' is a great iris with a great name.  It is very big and has beautiful colors.

Next we will continue our discussion of growing LA irises.