LIVING RAINBOWS: Irises in the Desert

Text and Photos by Preston Cox | Retail Nursery and Sales

For thousands of years, the iris flower has fascinated people. To the Ancient Greeks, it represented the goddess of the rainbow. Ancient Egyptian kings marveled at the exotic beauty of the iris. Many cultures used the iris for perfume or medicine. During the middle ages, the iris came to represent royalty. In Japan, irises were well known for their purifying elements and to ward off evil. Finally, in China, they were known as messengers who heralded summer's arrival.

Today, irises are still well known as one of the easiest perennials to grow in a flower garden or border. Irises are also one of the most varied in color and height. There are hundreds of varieties of iris in a staggering array of colors. As you walk through the Arboretum, you will find a fantastic collection of irises in the Demonstration Garden. Most of these are standard and tall bearded and put on a stunning show in spring.

There is another iris collection just past the Herb Garden. These irises are classified as arilbreds. Aril irises come from the Middle East and parts of Asia. They have been crossed with bearded iris to form arilbreds. These irises have the beauty and drought tolerance of the arils, and the hardiness and ease of care of the bearded.

Do irises grow well in the arid southwest?

Yes, irises grow exceptionally well in our desert gardens, particularly the bearded varieties. They are low maintenance, low water, and can take a lot of heat and neglect.

Successful Planting Tips:

Plant in the fall when temperatures drop below 90 degrees F.

They are best planted in areas with partial afternoon shade. Be sure your soil is loose and well drained.

Create shallow ditches and mound up the soil in the middle. Place rhizomes on top of the mound and run their roots down the sides, then backfill with soil until only the very top of the rhizome can be seen.

Gently water newly planted Irises so as not to wash them out of the ground.

Established Irises should be watered weekly in the summer, and once to twice a month in the winter. Adjust according to temperatures and weather.

Use a timed-release or diluted fertilizer in October and again in March to boost blooms. Make sure it is low in nitrogen and high in phosphorus.

Every 3 or 4 years, dig up irises and divide them by cutting the rhizomes apart, then replant. To prevent bacteria from killing freshly cut rhizomes, dip the cut tip into an antibacterial soap solution or a mild bleach solution.