Bearded Iris are propagated and planted as rhizomes, sideways-growing stems that shoot out laterally, just beneath the surface of the soil. Each new shoot begins to form new roots and shoots of its own. Plants use rhizomes for food storage. Ginger, turmeric, and Canna are all well-known rhizomes.

The history of iris flowers in North America is thought to begin with early European settlers who brought the bulbs to the new world. Iris flower origins have been traced to Virginia, where bulbs were probably planted in the 1600’s.

It is sometimes called Anderson’s Iris data set because Edgar Anderson collected the data to quantify the morphologic variation of Iris flowers of three related species.

Since most iris have rhizomes, start by looking for a rhizome. Look at the soil right at the base of the leaves. Some iris will have the rhizome sitting at soil level or even above soil level, as in the picture below. If you don’t see it, remove an inch or two of soil towards the center of the plant.

Irises multiply fairly quickly and when the plants become overcrowded they produce fewer of their lovely blooms. It is very easy to divide iris plants to rejuvenate them, and for the best display, bearded irises should be divided every three to four years.

A: After your irises have bloomed, you can indeed cut down the flower stalk; this process is known as “deadheading”. However, you should not cut down or tie up the irises’ leaves at this point, even if they are a bit unsightly.

Siberian irises grow well in cool, wet conditions and, though they thrive in full sun, they can also tolerate some shade.

The best time to plant and transplant rhizomatous iris is late July through September. Iris loves the heat and drier weather of summer and the summer dividing will reduce the incidence of bacterial soft rot. Most rhizomatous iris should be divided every three to five years.

As stunningly beautiful as irises are when they’re in bloom, they can be pretty uninteresting for the rest of the year. So imagine the wonder of having an iris reblooming in the same season — sometimes once more, sometimes twice, and depending on variety and climate, possibly several times.

Summer Care for Your Iris bed

1. Prune. Grab your best pruning shears, and cut back the spent flower stalks near the plant’s base.
2. Fertilize. Light fertilization in the summer bodes well for your iris plants’ health.
3. Weed. Weeds and grasses, left unchecked, will overwhelm your iris beds in little time.

summer

Reblooming Types “Rebloomers” (also called “remontants”) are irises that produce two or more flushes of bloom each year. “Cycle rebloomers” produce a spring crop of flowers, then lie low during summer, and grow and flower again in the fall.

Care of Iris After They Finish Blooming

1. Once the iris blooms have faded, cut the old stems down into the leaves.
2. As long as the foliage is green and attractive leave it in the garden.
3. If your iris didn’t flower well this year it could be that they are in too much shade or that they need dividing.

Bearded Irises Grow from Rhizomes Such plants also spread by rhizomes, and irises are no exception. While some rhizomatous plants, like bamboo, spread rapidly and even invasively, the iris spreads fairly gradually—one of its main virtues for gardeners. But, as iris rhizomes spread, they become crowded.

A number of bearded varieties bloom from early spring to early summer. Among beardless irises, many varieties in the Spuria subgroup bloom from late spring to midsummer. Some Siberian iris (Iris sibirica) and Japanese iris (I. ensata) selections bloom from mid-spring to early summer.

They should have plenty of air ventilation and it should be about 70 F. (21 C.). Leave the iris rhizomes there for one to two weeks.

Irises. If your dog eats irises, they may salivate, vomit, drool, have diarrhea or lose energy. This is because the iris contains several compounds that are toxic to dogs. Irises can also cause skin irritation.