Iris are beautiful perennial flowers that provide a brilliant color display every June. They can stand alone or be mixed with other perennials and annuals. Flowers come in a variety of solid colors (except true reds) and some two-color combinations. The clumping foliage is long and strap-shaped. Irises also come in a variety of sizes.
Bearded iris have furry strips on each of the falls (the 3 petal-like sepals that droop down). Japanese, Louisiana, and Siberian Iris have smooth falls and longer leaves.
Bearded iris prefer full sun but will tolerate very light shade. They must have good drainage. Plant bearded iris in the early fall. Thoroughly prepare the area by breaking up soil clumps, adding peat moss to aid drainage, and mixing in a balanced fertilizer such as Gardener’s Special. Use Myke’s for Annuals and Perennials to help establish a strong root system. Dig a hole about 6” in diameter and 6” deep. In the middle of this hole, make a mound of soil reaching almost to the surface level. Place the rhizome on the mound and fan the roots out. Fill in the hole with soil and firm around the roots. The planting depth is very important. The rhizome should rest just barely below the surface. If planted too deep, the iris will not bloom. Space the plants about 10” apart.
Older bearded iris plants can be lifted, divided, and replanted about every 3 - 5 years. This is best done in August. Mulch the plants lightly in the winter to prevent frost heaving. Remove dead leaves after the first hard frost to prevent iris borer eggs from wintering over. These borers are a common problem and cause the leaves to have a wet, streaked appearance. To control borers, spray every spring with Ferti-lome Borer and Bag Worm Spray when the new growth is about 3” high and then spray twice more at weekly intervals.
Japanese and Louisiana iris can be placed in moist areas, or even in standing water. Siberian iris can tolerate moist conditions and also well-drained soil conditions. Iris pseudacorus and Iris versicolor also do well submerged in water, by the water’s edge, or in moist parts of the garden. Transplant Japanese and Louisiana iris in fall or early spring. Divide them in the spring. They require sufficient moisture while they establish themselves.
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