Iris rhizomes are defined as underground stems. They mature in the ground in a horizonal position very close to the crown of the soil. These rhizomes will continue maturing and slowly proceed along just below the surface with a tremendous number of growth points. There are numerous other specimens such as cannas,calla lilies,water lilies. The bearded iris which will be addressed in some detail. You will be surprised that some iris are of the bulb family. The bulb forming species are helpful and of value in the gardening world with such well known varieties as the Dutch iris in demand year around for the cut flower industry. We will be discussing here various iris rhizomes that I consider the most significant in this long line of Spring flowers. Iris Rhizomes in many styles


The iris require at least six hours of full sunshine and sound drainage to accompany it. These plants thrive in a good fertile soil that has been deeply improved. The planting in dense clay demands closer awareness of the drainage problem. It wouldn't be good to detect,following a medium to heavy soaker,pooled water in the garden for more than thirty minutes after the rain has subsided. It maybe essential in this event to mound your iris rhizomes or plant them in a raised bed where the drainage can be better monitored. A little attention to the pH of the soil would also be beneficial.These rhizomes love a soil that is neutral. If planted in hot areas of the country,the plants should be placed where there is good afternoon shade. This Iris Rhizome Is Named The Gingersnap

This Iris Rhizome Should Have Been Named After Old Blue Eyes Going My Way

Wherever you buy the iris rhizomes they all measure one-half thick and two/three inch long pulpy rhizome. These rhizomes have short roots spreading out from the plant. It would be for the best if planted sooner than later. The soil needs to be replenished with ample amounts of compost. As I observed earlier,if the soil tends to be acidic,use dolomitic limestone to increase the Ph to neutral. As I have remarked numerous times before,you can obtain a soil testing kit from your local nursery or try your local agricultural center for testing.


The iris,specifically the bearded species,is to be planted in September and October. We will discuss several other species briefly later on. You must plant the rhizome high in the soil and make sure the roots are firmly grounded. The best way to achieve this is digging two trenches with a raised ridge and arrange the rhizome on the ridge and disperse the roots carefully to either side in the trenches. The next step is to fill the trenches with the soil and leave the top area of the rhizome barely under the surface. If you are coping with dense clay,then the rhizome should be placed so that up to one half of it is exposed higher than the soil. This should be followed by a firming up of the soil and then feed the rhizomes a welcomed deep drink of water.

A new iris bed had better be fertilized when preparing the soil before planting. The fertilizer should be low in nitrogen and conversely high in phosphorus and potassium. If you do not proceed with a test of the soil,then add one pound of 5-10-10 fertilizer per 100 square feet. The fertilizer must be worked into the soil and then allow the bed to rest before planting.

The problems to observe with your iris rhizomes is particularly poor flowering which is normally the result of way too much shade,apply too much fertilizer,planting the rhizomes too deep,or they have become over crowded and call for dividing. My rule of thumb for division is after three to five years. The Beautiful Cornation Anthem

The Dutch Iris A Bulb Iris

The Iris Rhizome entitled Blushing Crimson

If we consider these iris from left to right,we are first addressing the Siberian Iris and this one is named the Cornation Anthem. These are prominent landscape plants and exceedingly easy to grow. It features tasteful upright blue and green leafage that remains in first-class condition during the full growing season. They grow to a height of two to four feet. These Siberian Iris flourish in moist soil but do not care for standing water. They are also very tolerant of most average garden soils. They are one of the easier iris to grow in zones 3-9.

The Dutch Iris,as mentioned before,are produce from a bulb. These blossom early in the summertime in a lot of colors as pictured here in yellow. They grow on twenty-four inch stems and their preference is sun or afternoon shade in a well drained soil with a beneficial nutrient supply. These bulbs should be planted four to six inches in depth in September or October and in the south possibly as late as November. They Are good for zones 3-9.

The iris rhizomes continue with Japanese Iris pictured here and this one carries the name of Blushing Crimson. This special iris deviates from the others in that it commands a slightly acid soil. The blooms on these iris are uncommonly large,ruffled and flat in structure.They bloom approximately a month after the tall bearded iris. These iris rhizomes will thrive in a wet environment and even to the degree of shallow water. These iris are heavy feeders and command lots of organic nutrients. They require six hours of full sun. These are good for zones 3-9.

I have not covered the possibility of planting these iris rhizomes in containers.This is well worth another subject. I will perhaps cover this at a later date under container gardening. I will advise you when this has been done.

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