Your Guide to the Different Types of Iris Flowers

Most gardeners have heard of or grown Irises in their garden at one point or another. What most people don’t know is that there are more types of Iris flowers than just the coveted bearded Iris. In fact, there are about 200 different types of Iris flowers to choose from.

Like many other flowers, the name Iris is derived from Greek mythology. Irises are believed to be the rainbows that link heaven and earth. Iris, the messenger of the gods, links the gods to humanity. They believed she connected one end of the world to the other at the speed of the wind.

blue irisThe Iris has become a symbol for monarchs and royal families throughout history. The earliest example of this is the discovery of Iris artwork in a palace on the island of Crete from 2100 BC. The Iris is still used today as a symbol of royalty all over the world, and most people don’t even realize it.

The “Fleur de Lys” is the royal symbol of the Bourbon Kings of France. They symbol was also seen on the French flag before the French revolution. Today, the Fleur De Lys is often used to symbolize parts of Canada and even New Orleans, Louisiana. What you may not realize is that this symbol is actually a graphical representation of an Iris.

There are two main categories in which we categorize the different types of Iris flowers. Those two groups are Rhizome Irises and Bulbous Irises. All the different species, cultivators, and hybrids fall into one of those two main categories. You will need to understand these categories in order to understand how to grow Iris flowers.

Rhizome Irises

These types of Iris flowers have thick stems that grow horizontally under the ground. Some will only grow partially underground, and it is important that you do not bury them thinking they shouldn’t be exposed. After planting, they will produce sword-like leaves that overlap and produce what looks like a fan.

There are three popular Rhizome Irises that you may run into when researching how to grow Iris flowers: bearded, beardless, and crested Irises. These types of Iris flowers spread freely by producing underground stems. They are grown directly from existing rhizomes instead of from an Iris bulb.

Bulbous Irises

These Irises are grown from bulbs and require a dormant winter after they have flowered. These types of Iris flowers are typically smaller than rhizome Irises and produce smaller flowers. Many people find Irises at big box stores and think they are purchasing the larger Irises, just to get home and find an Iris bulb.

How to Grow Iris Flowers in Your Garden

Growing Irises is not difficult as long as you understand what they need. Once you figure out which of the types of Iris flowers you have, you can find out how to grow that kind of Iris. All Iris need well-draining fertile soil to begin with. Add some organic matter to the soil and work it at least 6 inches deep into the soil.

Purple and Yellow IrisDig a hole about twice the size of the rhizome or bulb that you are planting. Place it in the hole and then backfill the dirt that you removed and press it down by hand. This will leave the soil around the plant loose, giving roots an easier path to spread through.

One of the most important things to learn when discovering how to grow Iris flowers is not to cover the surface roots that they develop. They need to be exposed to sun and air so that they can dry out between watering. Failure to allow the roots to dry will cause them to rot and your Iris will rot and die quickly.

With most types of Iris flowers, it is important to cut the dead flowers off of the plant as soon as they start to fade. If you allow the petals to fall into the plant and decompose, you are asking for pests and disease to follow. Cutting them right away will also increase the chances of a second flower if you choose one of the reblooming types of Iris flowers.

Another thing to keep in mind when learning how to grow Iris flowers in your garden is to divide them every three to four years. They will reproduce quickly, making clumps of Irises in your garden. If you do not divide them and spread them out every few years, they will become overcrowded and stunt each other’s growth.