Few flowers are as user friendly to the weekend gardener as the bearded iris - "Bearded" refers to the presence of a furry strip on each of three drooping, petal-like sepals, called falls. The true petals are called standards and are upright. Flowers appear in late spring to early summer on stalks above the foliage. Offering carefree blooms in nearly every color of the rainbow, bearded irises are easy to establish and require a minimum of maintenance. Petals that vary in texture from the plushest velvet, to the finest silk, often on one flower, provide variety to suit almost every taste. Unlike most spring bulbs, bearded irises don't require a period of cold to produce blossoms, making them perfect for areas with mild winters. They are also extremely drought tolerant, good for areas with little or no summer rains. Bearded irises are not actually bulbs, but rhizomes, a kind of thick brown root. The rhizome can remain out of the ground for a week or two without serious harm, but the sooner it is planted, the better. Hardy in zones 3-9; the rhizomes need plenty of sun to bloom well and regularly.

 
Planting Irises

To plant your irises, choose a sunny spot in well-drained soil. Prepare the soil well by turning over the soil to a depth of at least 10 inches. Spread a balanced fertilizer (10-10-10) or (12-12-12) and work it into the top of the soil. Don't starve your irises or make them compete with nearby grass or weeds for food and water.
The roots must be buried firmly to hold the plant in place, but the rhizome should be near the surface. The rhizome itself should sit at about ground level. Growers differ as to whether it is best to cover the rhizome completely with a light layer of soil or to leave the tops a bit exposed. An easy way to achieve this is to dig two trenches with a ridge between them, place the rhizome on the ridge and spread the roots carefully in the trenches. Be sure to firm the soil tightly and allow enough for settling to keep the rhizome above any possible standing water. Then fill the trenches with soil, letting the top surface of the rhizome be just barely beneath the surface of the soil. If you have several plants, plant them at least a foot and a half apart, "facing" the same way. The rhizomes will then increase in the same direction, without crowding each other too soon. From the new parts of the rhizome, new bloom stalks will come up in later years and the flowers will be exactly as the original flower. This is called "vegetative propagation".

 

Dividing Irises

 

In about 2 or 3 years, the new rhizomes will begin to crowd each other and you will want to divide the plant, cutting the newer parts of the rhizome free from the old, which may then be discarded. When dividing, cut back leaves to one-third their length to keep newly planted divisions from being whipped by the wind and pulled from the soil. When digging, keep all plants carefully labeled with their names, for sure identification. It is wise to keep diagrams of your planting area to double check individual labels on the plants. This digging and separating is best done between one and two months after bloom season, usually in July or August. Soon after this the irises grow roots which help to hold the plant firmly during the winter.


Irises Coloring

With so many colors to choose from, most people buy their first irises in the spring from growers or garden centers where they can see the plants in bloom. Larger growers often have colored pictures of most varieties in their catalogs. But buying from smaller local growers whose catalogs may lack pictures is not difficult, if you know a little terminology. Irises are described by their parts, each of which can be a different color.
The three petals that grow upward on the top of the iris are called Standards. The three that hang down are referred to as Falls. The smaller often fuzzy or hair like parts in between are the Beard. If an iris is all one color it is called a Self. Bearded irises are among the few flowers to come in a true black. In fact, they come in every color except green and true red. Bi-tones as their name suggests are two shades of one color. A Neglecta is a blue or violet bitone. When the Standards and Falls are different colors they are referred to as Bicolor. A Varietata is a bicolor with yellow standards. An Amoena is a bicolor with white standards. A reverse Amoena has white falls and another color of standards. A Blend is one color blended into one or more others. The real mystery group is the Plicatas. The petals of Plicatas have light colored centers edged in a darker shade, but this allows room for quite a variety of combinations. Often the edges of a Plicata look like some one painted on the color with a stiff dry brush, leaving distinct spots of varying sizes. The oldest irises are often tall and simple four to five feet in height. Newer varieties may have ruffled or lacy (deeply ruffled) petals and tend to be in the two to three foot range.


Irises problems

A problem, which may plague damaged rhizomes, is bacterial soft rot. This may enter the rhizome through any wound. To get rid of soft rot, dig the rhizome, scrape out the affected tissue, allow it to dry in the sun, then dip in a 10-12% solution of household bleach for a few minutes. Rinse with water and allow to dry before replanting. As spring growth rises in the bearded iris patch, watch for collapsing fans or discoloration at the base of the foliage, or soft rhizomes. That tender first flush of growth is vulnerable to late spring frosts, which can fracture plant tissue, and rot can set in. It is wise not to fertilize until the threat of hard freezes is past, usually about four weeks before bloom. Another clue to trouble is a rather unpleasant odor from the rhizome. The quick and inexpensive fix is to scrape out the damaged tissue of the rhizome and drench the wound with liquid bleach. Another cosmetic and weather related problem which seems to show up when night temperatures are in the 50 degree F range, or higher, and combined with dew, is bacterial leaf spot, which is very similar in behavior to mildew and black spot (in roses and columbine), and the cures are the same. The old standby cure is Benlate (or Benomyl) which is applied in combination with a systemic insecticide for a "one spray cures all" approach. The latest "cure-all" is Ortho's Isotox IV plus Funginex in a combined single spray application every three weeks.

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