There isn't any flower prettier in spring than a bearded iris. In my garden, it blooms right at the beginning of June when most spring bulbs are finished and other perennials aren't blooming yet. It makes a great addition to the garden and the green leaves make a nice landscape plant later in the summer if the stalks are trimmed.
This perennial flower will return year after year if planted properly. You can find iris for sale at many plant companies online or you may be lucky enough to find a friend who will share some rhizomes with you. They spread rapidly, so you should be able to find a someone with some extras.
For best results irises should be planted in late July through September. You want to give the plants time to be rooted before the cold weather starts. It won't hurt the iris if they are planted in the spring months and I've done this several times. The recommended months are just better.
Where to Plant Your Iris
Iris will do well in soil that is well drained and close to a neutral PH. They need at least 6 hours of sun each day, but it is best if they get full sun all day unless you live in one of the southern states.
Plant the iris in soil with good drainage. They don't like to be in a wet spot. The rhizomes can rot if they are.
Plant the rhizome at or close to the surface of the soil. Give plenty of space between the plants. Allow at least 16-18" apart for good air circulation. Dwarf irises can be planted a little closer. This is one plant that you don't want to mulch since irises are prone to rot if the rhizomes are left damp.
After the rhizome is planted, water the plant. Don't over water the iris.
Snap off seed pods once the plant is finished blooming. The iris will thank you if you apply bone meal, or super phosphate on them. A 6-10-10 fertilizer works well too. Fertilizing in early spring and right after bloom is best. Never use a high nitrogen fertilizer on iris because it can cause the rhizomes to rot.
Keep the garden free of weeds. Prune the leaves in the fall to prevent diseases or pests overwintering.
Iris can become too crowded,because they multiply quickly. You want some distance between the plants, so they can get some air and don't crowd each other out. You will probably need to to divide them after about 3-5 years. If the plants get too crowded or large, they will stop blooming or not give good bloom anymore. Now it is time to share them with your friends or enlarge your bed.
The best time to divide in colder areas is by the end of August, but in warm areas this can be done as late as October.
You can now purchase iris that rebloom during the summer months. This is an exciting new discovery, because you get double the bang for your buck. If you can find some of these, be sure to plant some