Criddle enthusiastically shares her love of irises. "They are one of the easiest perennials to grow. Keep them clean, and keep the plant free from debris. Do not mulch them too heavily or let the mulch pile up on the rhizomes."

After they finish blooming, Criddle advises that they be divided if they're too crowded. She said the plants can be divided anytime from July through October. "You just need to replant them early enough to get established before cold, harsh weather comes," she said.

Irises are not susceptible to many pests, but there are two. The iris borer is not common in Utah, but occasionally we see it. It attacks the rhizomes and destroys them. Soft rot is another disease that rots the tubers. If you see rotted tubers, dig them up and throw them away. Don't try to compost them.

Irises can be planted almost any time. Try to prepare the beds a couple of weeks beforehand and add organic matter to help improve the soil.

Make the holes deep enough to accommodate the roots, but do not bury the rhizomes too deep. If you cover the rhizomes more than an inch deep, they will likely not bloom.

Another important aspect of growing irises is to plant them in the right area. They must get at least six hours of direct sunlight each day. More sunlight will help the plants grow even better.

Fertilize your plants sparingly. Use a low nitrogen fertilizer in the spring when the crocuses are in bloom. After the irises get done blooming, you might want to apply a light application of a general-purpose fertilizer.

When asked to name some of her favorite irises, Criddle hesitated. "For me, my favorite iris is the one that I am currently looking at."

"I always recommend that people plant several different types of iris to get a longer bloom season," she said. "Some iris bloom very early while others bloom much later. There are also some reblooming iris, but I have not have had too much luck with them except for the miniatures," she said.

When you refer to iris most people think of the tall bearded iris that grows 36-48 inches high. Other bearded iris types include the intermediates and the miniatures. These groups are defined by how tall the plant grows. But there are other types as well.

The spurias and the Siberian iris grow well in Utah; however, the Louisiana, the Japanese and some other types are more difficult to grow here.

Finding good iris varieties to grow in Utah is easy. The hardest task will be limiting your choices from the many hundreds of different varieties that are available.

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Larry Sagers is the regional horticulturist, Utah State University Extension, at Thanksgiving Point.