What Are They...Median Iris?

I am sitting here transfixed...by my window watching it rain--well actually pour down. This might not seem to be such an unusual thing, unless you know that we have had only .6 of an inch of rain since September 2010. Well, what am I doing sitting here…I’m going out to run in the rain! Will be back to work on this blog when it stops raining.

It is now 24 hours later and here I am; very happily back to my computer. My iris just got 1.44 inches of rain, all since I began working on this blog! Now I am watching out my window as a skinny red robin pecks at a peach that fell from my tree and a beautiful Baltimore oriole is eating off my hummingbird feeder and being buzzed by three hummers. I could be content to just watch it all, but I must begin this blog. It will be about my newest love in iris and I must tell you I am not an expert on them…the median iris. I planted my first medians four years ago, and I will tell you my progress at the end of this blog if you stick around to read it.  

Who's First In Line?

Median Iris –What are they? They are a group of bearded iris that are shorter than the tall bearded (TB) iris and taller than the miniature dwarf bearded (MDB). They bloom after the MDBs and mostly before the TB iris. They extend the iris bloom season with regal form, remarkable colors and patterns. Median iris are smaller and compact compared to the tall bearded iris. They make perfect plants for borders or in the front of your flower beds, and make ideal additions in rock gardens. Medians tolerate wide varieties of conditions being much more cold tolerant, withstanding strong winds, and strong rain downpours. When the Median Iris Society organized in 1948, five new classes of bearded irises (MDB, SDB, IB, MTB and BB) were added to the already popular TB iris class.

(click on images for a larger view)

The result of this effort was having four distinct bloom seasons starting with the miniature dwarf iris season, followed a little later by the standard dwarf iris season, and then later came the intermediate bearded iris season and finally the border (BB), miniature tall (MTB) and TB season.

Median iris come in four different classes.

1.   The crossing of I. pumila with the tall bearded (TB) iris resulted in what is known as the standard dwarf bearded iris (SDB) type. The SDBs are 8–15” in height with blooms that are 2-4” in width. The SDBs bloom after the miniature dwarf bearded iris and slightly into the intermediate iris bloom season. They have thick attractive mounds of sword-like green leaves that grow throughout most of the season. The SDBs have an enormous variety of colors and patterns and that combined with a great vigor and ease of growth make them a wonderful edition to all gardens.

2.   Then there are the crosses of SDBs with TBs (or TBs with species iris) that grow into the intermediate bearded iris (IB). The IBs are 16-27” tall with flowers that are 3½-5 wide. The IBs fit both in size and bloom time between the SDBs and the TBs. They are very hardy growers, dependable bloomers, disease resistant and can withstand high winds, sudden freezes, and other unexpected weather changes. They come in the full range of colors and combinations as the TBs.

3.   Next we have the miniature tall bearded (MTB) iris that are 16-25 inches in height with very slender dainty stalks and nicely branched stalks with flowers whose combined width and height is not more than 6” total. They started as diploid runts of iris that first appeared in TB gardens. Then hybridizers used I. aphylla's, a family of shorter tetraploid species bearded irises that increase branching and have smaller flowers than TB’s. They started by crossing I. aphylla with selected BB and short TB until they developed a tetraploid MTB that met the same requirements as the diploid MTB. The MTBs have a very pleasant fragrance that is essential in this lovely iris also aptly named the table iris. The flowers are less ruffled and more tailored than the TBs. The boom season is later the IBs and about the same as border bearded (BB) and TB. This class is ideal for floral arrangements. MTBs are the best branched of the medians, and fit nicely in the garden.

4.  The class of medians known as border bearded (BB) started as small versions of TB iris that did not overpower other plants in an ornamental bed, and did not blow over in high winds, and worked well in flower bed borders. Over the years since BB became a class, hybridizers have made great strides in the improving the vigor, consistency of height, flower proportion, colors and color patterns. Bloomstalks of BB should be 16" to 27.5", the width of the flowers should not exceed 5”, the height of the flower should not exceed 8.5"and they should bloom along with the tall beardeds. BB iris look like and bloom like the TB iris but their size are smaller and properly balanced for its smaller size with erect fans that do not obscure the blooms.

I am Debbie Strauss, a newbee in the median iris world. I am a member of The American Iris Society and just became the director in charge of the silent auction at the National Conventions. I am a Median Iris Society member and their new fundraising chair. I live in far West Texas in a desert-like environment. TB iris do wonderful here, especially if you stress them out before planting the new rhizomes (if you purchased them from anywhere except West Texas). Four years ago our local iris society hosted a fall regional convention for Texas; I was the iris auction chair. I wrote to every hybridizer I could and sent them a little money and asked for iris for our regional auction. I was not particular about what they sent and I received many many iris. Hmmm…lots of medians…their colors and patterns were too tempting, so I bid on and won many of them…I planted them and the first year they all did well and multiplied and at least half of them bloomed. Then the second year…I can’t even describe how delighted I was when the SDBs were lovely large clumps and bloomed beautifully. If you look at the photos below, you will see why my first plantings of median iris made me a big fan of the wonderful median iris classes.

The pictures below are from two year clumps! They are growing in my West Texas soil that is a very alkaline sandy mix. They are planted along side my hot driveway, with a large stinky hedge behind them. We get very little rain, only a few winter days below freezing, and rarely have below zero temperatures. We have wind with spring gusts from 30 – 60 mph nearly every day. To make it really bad; we had 68 days this summer of over 100-degrees and until last week only .6 inch of rain since last September. So for any iris to grow and prosper here…takes a miracle…well a very good hardy plant anyway. 

Even though the TB irises are the most popular iris among the AIS membership, I believe it might be because conventions and shows are scheduled around the bloom season of the TB iris. Perhaps like me, many people have not given the medians a chance. Even though only one border bearded iris, 'Brown Lasso' and one Intermediate Bearded iris, 'Starwoman,' have been awarded the AIS’s highest award, the Dykes Medal, I think those numbers will increase. Here are pictures of these two wonderful median Dykes winners.

Brown Lasso

I am predicting with all the stellar work of the median iris hybridizers median iris popularity will increase leaps and bounds in the near future. If you have not yet planted a median iris or two, take a leap of faith, look through the many colors, patterns, sizes, and bloom times and get started. Oh, by the way… I took "Best of Show" two years with a median iris! They thought they scheduled the show for TB bloom!