Book Review: Dwarf and Median Bearded Irises

by Tom Waters

Dwarf and Median Bearded Irises: Jewels of the Iris World

Kevin C. Vaughn

Schiffer Publishing, 2022

ISBN 978-0-7643-6389-4

144 pages

Books about bearded irises don’t come out nearly often enough, in my opinion. It’s been over a decade since Kelly Norris’s beautiful A Guide to Bearded Irises made its appearance, and it is especially exciting for some of us to see a book devoted to the dwarf and median classes. Whereas the heart of Norris’s book was profiles of favorite individual cultivars in all the different classes, Vaughn focuses on the classes themselves: why we grow them, where they come from, and where they are going.

The book has a simple and clear organization: a chapter for each dwarf and median class, a general chapter on culture, and a chapter on hybridizing. The last is quite innovative in books of this type. Most horticultural titles address readers solely as consumers—purchasers and growers of garden plants. But Vaughn is a lifelong hybridizer, and his enthusiasm for this hobby is infectious. It adds a whole other dimension to how we appreciate our irises, and Vaughn assumes that many of his readers will want to share this with him.

The chapters on each class set forth the distinctive qualities and uses of each, selling the reader on what each has to offer. But Vaughn goes further, giving us a historical overview of the development of each class. This dovetails nicely with the corresponding chapters in The World of Irises* (edited by Bee Warburton and Melba Hamblen, 1978), bringing each class up to present day. The work of important hybridizers who contributed to the development of each class is noted and summarized. This is an important contribution. Those who have been deep in the iris world for decades know this history, which is sort of a shared experience, transmitted by word of mouth and personal correspondence; but this book records that history and makes it accessible to newcomers.

The chapter on culture takes a very welcome, fresh approach to the subject. Instead of repeating the familiar instructions that seem to have originated a hundred years ago with gardeners in the UK and New England, Vaughn takes us on a tour of his own gardening experience in Massachusetts, Mississippi, and Oregon, and relates practices of other gardeners he has known. This opens up the subject, putting forth lots of good ideas without pretending there is a one-size-fits-all recipe.

The hybridizing chapter was of special interest to me. It should be noted that an entire book could be devoted to this subject, so this presentation is necessarily condensed. Vaughn refers readers to the chapter by Kenneth Kidd in The World of Irises*, and indeed I think it is best to use these two resources in tandem. Total newcomers will need to work some to connect the dots as they read Vaughn’s chapter. The effort is one that pays off, though, as Vaughn has a lot to share with us about how a backyard gardener can approach a hybridizing program and what the special challenges are for working in each of the dwarf and median classes.

To sum up, this book makes a fine addition to the library of anyone interested in dwarf and median irises, particularly those of us sufficiently immersed in an iris obsession to appreciate this book’s attention to hybridizing and to history.

*EDITOR'S NOTE: The World of Irises book is now out of print, but used copies can be found online. Wayne Messer and Bob Pries have also transcribed select book chapters for Iris Encyclopedia. AIS is always looking for volunteers who can type existing content into this online library. If you are interested and available for transcription projects like this, please reach out to Bob at bobpries3@gmail.com.

Proportion, Proportion, Proportion

 by Tom Waters

There is no excellent beauty that hath not some strangeness in the proportion.

                —Francis Bacon

It seems like devotees of the dwarf and median irises, myself included, are always talking about proportion. All the parts of the stalk, we are told, must be in proportion: the height and width of the flowers, the height and thickness of the stalk, even the leaves. Indeed, the American Iris Society’s Handbook for Judges and Show Officials gives measurements and ratios to define proper proportion for each class.

I’d like to raise a philosophical issue about proportion, and how it relates to two iris classes in particular, the border bearded (BB) and miniature dwarf bearded (MDB). These two classes face a similar problem: most BBs are produced by crossing tall beardeds (TBs), and most MDBs are produced by crossing standard dwarf beardeds (SDBs). Since the genetic background of these classes comes mostly from a different, taller class, it is not unusual to find flowers that are large, even when the height of the stem is short. Purists are very bothered by this situation, but short irises with large flowers seem to be popular with iris lovers and even judges. Are the many people who enjoy large-flowered BBs and MDBs just wrong? Should they know better?

The philosophical issue is this: is “good proportion” objective? Is there some numerical ratio of stem, flower, and foliage that is aesthetically optimal? Or is it just in the eye of the beholder? If it is just a personal, subjective preference, then the admonitions in the Judges' Handbook start to seem a bit arrogant and elitist. The classic example of a subjective judgment becoming judging gospel is the case of haft marks. In the mid-20th century, haft markings were the “fault” that everyone seemed obsessed with in TB irises. Yet, what if I think haft marks are interesting or pretty? Is this any different than preferring yellow to blue, or preferring plicatas to selfs? The condemnation of haft marks reflects the struggles of hybridizers. In those early years, it was very difficult to breed a true, clean, self-colored iris. Haft marks seemed to always turn up and distract from the desired purity. So the frustration felt by hybridizers was transformed into an esthetic standard that was promoted as something objective and universal. Once clean selfs were achieved, then people could start to enjoy haft marks for being “something different”!

Many, many “rules” that are enshrined in the Judges' Handbook are relics of the personal goals and frustrations of earlier generations of hybridizers, even though they are presented as objective aesthetic truths. I think proportion is one of those things. I say this despite the fact that I, personally, dislike large-flowered BBs and MDBs. If a BB blooms in my garden with TB-sized blooms and thick, coarse stalks, it does not stay here another year, no matter how pretty the color or form. However, in all honesty, I have to describe this as a personal preference.

Allium karataviense

If there were some objective, universally valid, proportion of bloom to stalk that looks best to everyone, then we would expect it to apply to all kinds of plants. But in fact, we enjoy flowers with all different ratios of bloom size to stem height, without thinking twice about it. Consider two alliums I grow: A. karataviense produces enormous globular flower heads right at ground level. I enjoy it immensely. A. caeruleum produces small, airy blue flower heads on tall slender stalks. I enjoy it also. These two could not be more different. And neither has the proportion of a “good” bearded iris. In fact, I think an iris proportioned like either of the alliums would inspire revulsion in a typical iris judge.

Allium caeruleum

It may seem like I am now arguing for a free-for-all approach to proportion. If it is all subjective, why should we worry about a BB with TB-sized flowers or an MDB whose bloom is twice as wide as the height of the entire stem? Perhaps judges should focus on more objective things, like plant vigor and bud count, and let people enjoy different proportions, just as we enjoy different colors?

No, that is not the approach I favor, although I think the argument should be made from time to time to provoke thought and debate. I believe there is a good reason for harping on proportion in the dwarf and median irises, but I don’t think it has anything to do with some objective, universal standard of beauty.

'Solar Sunrise' (Black, 2019),
a BB whose proportion I like.

What then? If small-flowered BBs and MDBs are not objectively superior to large-flowered ones, why should we care at all? I think the answer lies in something else: class identity. Consider this: although they fall in the same height range, miniature tall bearded (MTBs) are “supposed” to have smaller flowers and more slender stems than BBs. If one proportion is more attractive, shouldn’t all classes aspire to that same proportion?

To most median aficionados, the answer is obvious: each class has its own aesthetic ideal. We like the fact that BBs look different from MTBs. They are like two different styles of music. In our minds, we may have a picture of the ideal, the prototype, as it were, for each class. It is these mental prototypes that give each class its identity, its center of gravity in the great sea of diversity that hybridizers have produced for us.

So I think what we are complaining about when we complain about out-of-proportion BBs or MDBs is the erosion of the identity of the class, the weakening of the mental prototype. The reason I have singled out BBs and MDBs is that the irises in these classes are mostly “spill-overs” from TBs and SDBs, respectively. There is a relentless pull on these classes to merge together with the larger classes that give rise to them. If a BB is just a TB that is short, why not call it a TB?

'Icon' (Keppel, 2008)
an MDB whose proportion I like.

Some have sought to strengthen the identity of these classes through breeding. Lynn Markham’s BBs
were produced intentionally to reinforce the distinct identity of the class. Ben Hager used a similar strategy to reinforce the identity of the MDB class. These were valiant efforts, but they were not sufficient to turn the tide. So many people are crossing TBs that the “accidental” BBs that emerge from TB crosses far outnumber the “intentional” BBs that are produced by the small number of breeders who are interested in the class as an end in itself. Exactly the same is true of the MDB class.

I wish I could end on some profound revelation or recipe for solving the conundrum of these classes, but I don’t think there is one. What it comes down to is simply this: do we (the entire iris-loving public, hybridizers, and judges) care enough about the identity of these classes to insist on maintaining their integrity? Perhaps we don’t. It’s not obvious that we “should”, after all. If we like the irises we’re growing, even when they depart from that mental prototype, maybe that is fine. Collective opinion is not something that can be easily predicted or controlled. It just is what it is.

But if nothing else, perhaps we can shift the language of the conversation a little. Instead of talking about “good” or “bad” proportion, perhaps we can talk instead of class identity. That seems more accurate and to the point.

 

Bearded Iris Species for the Garden

 by Tom Waters

Most of us are quite familiar with the gorgeous hybrid bearded irises grown in so many gardens around the world. Whether dwarf, median, or tall bearded, these irises are the great show-stoppers of the springtime iris parade. Every year, hybridizers introduce new varieties, so there is a never-ending stream of new colors, patterns, and flower forms.

But before hybridizers took an interest in irises - and that was scarcely more than 100 years ago - bearded irises in gardens were much like irises in nature. Yes, bearded irises are wildflowers in Europe and western Asia, where numerous different species grow on hillsides or in valleys without gardeners to care for them.

These wild bearded irises are of interest to some iris growers, for a variety of reasons. Some of us are just attracted to wild flowers, and like to see the plants as nature made them. Others are students of iris history, and it is these bearded species that are ancestral to our modern hybrids; growing them is like tracing the roots of our family tree. Others are hybridizers, curious to explore the untapped potential of these species.

Here is just a smattering of bearded iris species that may be of interest, with an emphasis on those that have been mentioned frequently in books and articles or that have featured prominently in the development of our modern bearded iris hybrids.

Iris pallida,
a form with variegated foliage

Iris pallida is a European tall bearded (TB) species, with light blue-violet flowers and straight stems with branching clustered near the top. To my eye, it is the most stately of all the bearded iris species.

I. variegata, another European species, is smaller, similar to  miniature tall bearded (MTB) irises in size, with zig-zag stems and distinctively colored flowers with yellow standards and falls marked in wine-red or brick-red.

These two species are probably the sole ancestors of the diploid tall bearded irises grown in gardens in the 1800s and early 1900s. They hybridize in nature, and these natural hybrids (amoenas, bitones, and blends) were collected by flower lovers and grown in European gardens. Any modern TB iris that has yellow (or pink or orange) coloration owes its color to I. variegata.

Iris variegata

The other wild irises important in the development of the modern TBs were a range of different tetraploid plants from various locations in the eastern Mediterranean. These include I. cypriana, I. trojana, I. mesopotamica, and some named clones such as 'Amas' and 'Ricardi'. All are purple bitones and large, well-branched plants. The botanical status of these is not as clear as might be, but every modern TB descends from them in some fashion. It was hybridizers of the early 20th century who crossed the colorful diploid pallida/variegata hybrids with these large tetraploids to create the modern tetraploid TBs that have become the most popular and widely grown of all irises.

Iris aphylla

Moving down in height, we come next to I. aphylla, a species from eastern Europe that is usually similar to standard dwarf bearded (SDB) or intermediate bearded (IB) irises in height, but copiously branched, the lowest branch usually emerging right at ground level! The flowers are dark violet, and beards usually bluish. It has been used in two different ways in breeding modern bearded irises: first in breeding "black" TBs, and then later in the work of Ben Hager and others creating the tetraploid MTBs. See my earlier blog post Our Debt to Iris aphylla.

In the realm of dwarf species, the earliest known to western European gardeners was I. lutescens (once called I. chamaeiris), which is native to the warm Mediterranean areas of Spain, France, and Italy. It was the basis for our garden dwarf bearded irises until the 1950s. Its height varies, spanning the modern MDB and SDB classes and sometimes growing even a bit taller. Colors are yellows, violets, whites, and blended and bitoned versions of those colors. See my post Iris lutescens: The Dwarfs that Time Forgot.

Iris pumila seedlings

The most important dwarf species in the development of modern dwarf and median irises is the species I. pumila, native to cooler, higher regions of eastern Europe. It is quite tiny, usually only about 4 inches tall, with blooms that appear almost stemless and  spring straight from the rhizomes. It has an extensive color range, from white to blue, purple, rosy, and yellow, usually with a darker spot of violet, red, or brown. It came to the attention of iris breeders in western Europe and the US rather late, in the mid-20th century. Once "discovered," however, it became a power player in iris breeding. I. pumila, when crossed with TBs, produced the modern SDB class, and through them the modern MDBs and IBs as well. See Iris pumila: A Tiny Treasure.

Iris reichenbachii grows wild on the Balkan peninsula, where it exists in both diploid and tetraploid forms. The flowers are rather long in form, and most are either a dull yellow or a grayish violet. This species is notable in the history of iris breeding for introducing the "dominant amoena" gene into the TB gene pool through the work of Paul Cook. Most modern bicolors have I. reichenbachii back somewhere in their family tree. See The Untapped Potential of Iris reichenbachii.

Iris reichenbachii

Also worthy of note is I. reichenachii's diploid relation, I. suaveolens (once called I. mellita). It is smaller than I. reichenbachii, but otherwise similar. It is noted for its sickle-shaped leaves, in some forms edged in a narrow line of red-violet pigment.

I hope this line-up of bearded species has piqued your interest. They are nice additions to the garden for anyone who is curious about where our garden iris "came from" or is attracted to the simple beauty of wildflower irises. One sometimes finds a few bearded species available from commercial iris growers, but more are consistently available through various seed exchanges from societies like the Species Iris Group of North America, the Scottish Rock Garden Club, the British Iris Society, or the Dwarf Iris Society.

Why not "go wild" and try some bearded species this year!

What is a Dwarf Bearded Iris?

…and why are dwarf lovers so persistent?

 Tom Waters

'Icon' (Keppel, 2008)

In the beginning, there were no class definitions. The meaning of the term “dwarf bearded iris” was taken for granted, as all the ones being grown in gardens were similar in appearance and distinct from their taller relatives.  If you were botanically inclined, you could turn to a reference like W. R. Dykes’s The Genus Iris to get a list of dwarf bearded species, and safely assume that your garden dwarfs were hybrids or forms of those species.

The 1939 AIS Checklist attempted to be somewhat more helpful by giving a height range in addition to the list of species, setting the boundary between dwarfs and intermediates (which were stated to be hybrids between dwarf and tall bearded irises) at 17 inches. This doesn’t make sense, though, if it is taken as a definition, rather than just helpful descriptive information. What if two of those dwarfs species were crossed and produced a hybrid over the limit? Or what if a dwarf and tall were crossed and produced a hybrid under the limit? Giving both a definition in terms of ancestral species and a definition in terms of height is inviting contradiction unless it is clear whether ancestry trumps height or vice versa.

Perhaps in recognition of this, the AIS adopted a new classification in 1947, based decisively on ancestry. A hybrid involving only dwarf species would always be a dwarf; a hybrid involving only tall species would always be a tall. A hybrid involving both dwarfs and talls would usually be intermediate, but might be deemed either dwarf or tall if that was the group it most resembled. Although this last provision was strangely vague, the definition at least allowed hybridizers to cross dwarfs amongst themselves and register the progeny as dwarfs, without worry about a height limit or other factors.

This classification system was introduced at the same time as Walter Welch was organizing the Dwarf Iris Society (then called the Dwarf Iris Club) and stirring up interest in dwarf hybridizing, so there may have been some impetus to clarify definitions for this reason. Although dwarfs had been widely grown in both Europe and North America for as long as tall beardeds, they had not historically received a great deal of attention. Gardeners took them for granted, and although new hybrids were introduced from time to time, there were no hybridizers who focused on them exclusively or had planned breeding programs solely to produce new dwarfs. Welch turned that around, first by organizing a program of round robins, whereby enthusiasts (many of them recruited from gardening clubs and publications, not just iris societies) could discuss dwarf irises by mail, and then by creating the Dwarf Iris Club in 1950. I believe this was the first specialist iris society devoted to a particular type of iris. With the blessing of the AIS, the Dwarf Iris Club even trained and appointed its own judges, just for judging dwarfs!

In 1951, something happened that put the class definition under unprecedented strain. Paul Cook (a friend and correspondent of Walter Welch) introduced the first three irises of the type we now know as standard dwarf bearded (SDBs), from crossing the tiny dwarf species Iris pumila with tall beardeds. As a dwarf x tall cross, a strong case could be made that these new irises were intermediates, and indeed that is how they were registered at the time. But they were no taller than many of the dwarfs being grown at the time, so this might seem a little inconsistent. Welch and the DIS focused attention on the presence of a small branch in most SDBs, asserting that a branch was disqualifying for being considered a dwarf. Oddly, the list of dwarf species that AIS had been printing and reprinting for many years included amongst the dwarfs Iris aphylla, which is copiously branched.

The 1954 classification made
the dwarf people grumpy

Recognizing that the future might hold even more examples of such “problem children” from newfangled hybridizing experiments, the AIS suddenly reversed itself in 1954, offering a classification based entirely on height, with ancestry deemed irrelevant. This makes sense in a world where parentages have become complex or uncertain. Height is something that can be established with a ruler. Now the boundary between dwarfs and intermediates was set at a rigid 15 inches, regardless of what species the plants had come from or what characteristics they had. Welch and the DIS refused to accept this definition, appalled at the thought of 15-inch branched “intermediates” masquerading as dwarfs! Welch could be an opinionated and difficult person under the best of circumstances, and now he and his supporters had a righteous cause for contention. This caused a rift between the AIS and the DIS whose repercussions are still playing out today. From 1955 until 1973, the DIS had its own awards system, issuing the Welch Award in competition with AIS’s Caparne Award, despite the fact that it tended to be the same irises winning both awards.

Other classification issues were percolating at this time as well. There were movements afoot to recognize the so-called “table irises” and “border irises” as separate from both TBs and IBs. A committee was put together to study all these issues and propose a solution. In 1958, the AIS adopted a classification that has remained in place (with minor modifications) to this day. The dwarfs were separated by height into miniature dwarfs and standard dwarfs, with the dividing line being 10 inches. The border bearded class was created for short TBs, and the miniature tall bearded class was created for the table irises. The DIS had no interest in any of these new classes, not even the SDBs, and so the Median Iris Society was formed with the mission of promoting the five new classes between MDB and TB. A peculiar quirk of this development is that standard dwarfs are considered medians, not dwarfs, in apparent contradiction with their name.

'Alpine Lake' (Willott, 1980)
a classic MDB from SDB x pumila breeding

The 1960s and 1970s were perhaps the most exciting time in the history of dwarf iris development. Although the SDBs themselves were deemed too large to be considered true dwarfs, they had an enormous impact on breeding. Dwarf enthusiasts crossed the SDBs back to I. pumila, producing many charming hybrids, earlier blooming than the SDBs and quite distinctive in appearance, with ¾ of their genes coming from the dainty I. pumila. This became the standard cross to produce MDBs. The class was rounded out by selections of pure pumila ancestry, as well as hybrids from pure SDB breeding that happened to be small enough to fit the definition of the MDB class. These “runt SDBs” did not always meet with the approval of the dwarf purists, although there are a number of fine irises in this category. Indeed, in recent decades these MDBs from pure SDB breeding have come to quite dominate the class, in terms of sheer numbers as well as awards.

'Little Drummer Boy' (Willott, 1997),
an MDB from pure pumila breeding

In light of this history, one can understand why the DIS has remained rather protective of the little irises under its charge, and reluctant to muddle the boundary between the dwarf MDBs and the median SDBs; the dividing line between the classes was reduced to 8 inches in 1976, in part to protect the MDB class from SDB interlopers. It also explains the misgivings of many DIS members about merging with MIS, which has been suggested on a number of occasions. Any of the median classes might seem to have more cause to have its own society, given that they all have more new irises introduced each year than does the MDB class. Yet our history has set us apart, and perhaps it is the very fragility of the class in the face of the much larger (in numbers as well as stature!) median classes that inspires a certain connoisseur’s devotion amongst us.

'Pearly Whites' (Black, 2014),
an MDB from pure SDB breeding

In 2018, the DIS seemed on the brink of demise, with the president and vice president resigning, and the officers voting to merge with MIS. Rather miraculously, this was reversed in 2019, with a grass-roots rallying of the troops under the enthusiastic leadership of Charlie Carver, historic iris conservation advocate and devotee of MDBs. We now once again have a functioning society with a full slate of officers and a content-rich newsletter in final preparation for publication early this year. If you love dwarf irises and would like to be part of this renaissance, the DIS would love to hear from you!

Borderline Cases

by Tom Waters

There are three classes of median irises that span the interval between the standard dwarf bearded (SDB) and tall bearded (TB) classes. The intermediate bearded (IB) are mostly the result of crossing TBs with SDBs, leading to plants intermediate between the two, both in height and in bloom season. The miniature tall bearded (MTB) come from varied backgrounds, but must meet exacting standards of delicacy in height, flower size, and stalk proportions. The final class, the border bearded (BB) are derived almost exclusively from the TBs, but with height less than the 70 cm (27.5 inches) that is the boundary between the BB and TB classes.

The BB class is unusual in that it has no real “center of gravity” of its own; rather it represents the smaller “tail end” of the TB class. Many BBs are registered at a height of 27 inches, just barely below the upper limit of the class, and are hard to distinguish in practice from TBs at the lower end of the TB height range. One might ask if there is really a need to place such irises in a separate class.

Proponents of BBs have long had a vision of the class that sets it apart from the TB class. An ideal BB is not just a TB that is an inch or two shorter; rather, an ideal BB is a reduced TB in all its dimensions and proportions, including foliage, branching, flower size and form. While it is not intended that they be as delicate as MTBs, they ought to be “halfway there”, as it were – they should be esthetically medians, instantly distinguishable as diminutive and elegant irises in their own right. Part of their value comes from being useful in garden design in situations where TBs would be out of scale or overwhelming. They should be more about charm than grandeur.

'Brown Lasso' (Buckles by Niswonger, 1975),
BB (22 inches), American Dykes Medal, 1981

Some of the best median hybridizers have pursued this ideal with great care, selecting plants for introduction that are modestly proportioned, perky, and might more easily be mistaken for IBs or MTBs than for TBs. Early BBs like ‘Frenchi’ (B. Jones, 1959) and ‘Tulare’ (M. Hamblen, 1961) were exemplars of this ideal in their time, as was ‘Brown Lasso’ (Buckles by Niswonger, 1975) which was the only BB to win the American Dykes Medal. ‘Cranapple’ (Aitken, 1995) is a worthy example of more recent vintage.

 This is difficult work, and not always appreciated; many people buy BBs just as they do TBs, by looking at the catalog “glamor photos” of single blooms and choosing exciting colors and patterns, with little attention to plant proportions or esthetics. A large, blousy iris with the latest TB color pattern that does not meet the BB ideal may sell more than a carefully selected, lightly ruffled, charming BB in an unexceptional yellow, violet, or white.

One might argue that this doesn’t matter in the big picture of things. People like what they like, and if they enjoy an iris, who cares about its failure to meet some elitist ideal?  On a case-by-case basis, I think that is a valid perspective. Where it becomes problematic is when the notion of the class becomes so blurred that it ceases to convey anything clear to gardeners, and those seeking smaller, well-proportioned medians can’t trust the BB designation as meaningful.

'Oops' (Jim and Vicki Craig, 2003),
a BB from tetraploid MTB breeding

We all have a role to play in maintaining the distinctiveness of the BB class. Hybridizers can work more with lines that are intentionally devised to produce BBs, rather than taking most of their BB introductions from crosses intended to produce TBs. Tetraploid MTBs and smaller bearded species can be used to “tame” the TB genes and keep plants in scale.

Judges must strive to be more scrupulous in maintaining the standards of the BB class. Alas, color novelty and hybridizer reputation often bias judges away from a more sober consideration of shape and proportion.

Finally, buyers can reward hybridizers who keep the BB ideal in mind. Best of all is to buy BBs you have seen growing in a garden, and which you know to be consistently diminutive and in proportion. If you do buy “sight unseen” (as I often do), give preference to BBs registered in the 20-24 inch range, rather than 26 or 27 inches, as so many are. I also check pedigrees, looking for a preponderance of BBs, MTBs, or SPX irises in the background of a new BB. Finally, even a single-bloom photo can convey information about the scale of the plant, if you know what to look for. A bloom that is perky, flared, and not too ruffled is more likely to be in scale than one that is more flamboyant but not so flaring.

I have chosen not to use this blog post to give examples of modern BBs that I think are particularly fine or particularly poor examples of the class ideals; that is for each person to decide for themselves.

The BB class need not be just a spillover for short TB seedlings; it has much to offer the discerning gardener. Wonderful irises come in all sizes!

If you found this post interesting, please check back in January, when noted hybridizer Kevin Vaughn offers his reflections on the history of the BB class and promising avenues for its future development.

Our debt to Iris aphylla

Tom Waters

I. aphylla

The European bearded iris species Iris aphylla has contributed to the development of modern bearded irises in a number of different ways. It still remains of considerable interest to hybridizers, particularly those working with the median classes.

The species is native to much of eastern Europe, with a range extending farther north than other bearded species. This makes it thoroughly winter hardy. It goes completely dormant in winter, losing all its leaves right to the ground. (The Latin word aphylla means "leafless".) The flowers are violet, although some recessive white and other off-color forms exist. The flowers themselves are not particularly glamorous, being often narrow and of poor substance. One of its most distinctive characteristics is prolific basal branching, with long branches starting low on the stalk, not infrequently at the point the stalk emerges from the rhizome. It varies in height, with forms as small as 30 cm and as tall as 60 cm or more. Both wild-collected forms and garden cultivars of the species have been registered and circulated.

I. aphylla 'Slick' (Lynn Markham, 2003)

Happily, I. aphylla has a similar chromosome complement to that of our modern tetraploid tall bearded (TB) and border bearded (BB) irises. This means it can be crossed with them to produce fertile seedlings that can be continuously worked with and improved for as many generations as one likes.

Early breeders showed little interest in medians, and simply worked I. aphylla into TB lines. It was found to contribute two interesting traits: an intensification of violet flower color, and blue or violet beards! Many early approaches to black in TB irises, such as 'Sable' (Cook, 1938) and probably 'Black Forest' (Schreiner, 1948), derive from I. aphylla. It is also behind many whitish or light blue TBs with blue or violet beards. In these irises, the dominant white found in TBs interacts with the intensification of violet pigment from I. aphylla.

When enthusiasm for median irises blossomed in the 1950s, with the formation of the Median Iris Society and the establishment of the four classes of median irises, creative breeders began to consider the potential of I. aphylla to add variety to these classes.

'Tic Tac Toe' (Johnson, 2010)
tetraploid MTB descended from I. aphylla

The most ambitious of such undertakings was Ben Hager's project to create tetraploid miniature tall bearded (MTB) irises. This class had been created with diploids in mind. Most TB irises from the 1800s and early 1900s were diploid, with a daintiness that was lost when tetraploids came to dominate. Early MTB breeders had taken these daintier TBs and bred them for even smaller size and greater delicacy. The MTBs were promoted as subjects for flower arranging. Tetraploid TBs, however, showed more different colors (such as tangerine pink), wider form, and better substance. Could these traits from the modern TBs be transferred to irises dainty enough to qualify for the strict requirements of the MTB class? Hager set about proving that they could. He crossed I. aphylla with small TBs and BBs, and then kept breeding toward the MTB requirements. After many generations of work, he established a line of tetraploid MTBs. Although these did not look exactly like the diploid MTBs (I. aphylla yields straight, upright stalks with vertical branching, whereas diploid MTBs often have a more zig-zag branching style), they had an appeal all their own. The first pink MTBs were Hager's tetraploids from I. aphylla.

'Saucy' (Craig, 1998)
tetraploid IB descended from I. aphylla

Hager's work was carried on by Jim and Vicki Craig, who combined Hager's irises with their own crosses involving different forms of I. aphylla. They introduced not only tetraploid MTBs, but BBs and IBs from the same breeding lines. This enhanced the variety of all three classes. They even produced a couple that were small enough to qualify as standard dwarf bearded (SDB)!

Others have worked with I. aphylla over the years, and continue to do so. Some hybrids that a relatively close to the species itself have been registered in the SPEC-X category. Paul Black's "small-flowered TBs" owe a debt to I. aphylla.

This species has contributed a great deal to the variety we find in both TBs and medians today. Do you grow any irises with I. aphylla ancestry? I'd wager you do!

'Night Mood' (Lynn Markham, 2003)
SPEC-X from 'Blackbeard' X I. aphylla 'Dark Violet'

The Untapped Potential of Iris reichenbachii

by Tom Waters

Today's post is all about an underappreciated bearded iris species, Iris reichenbachii. The name, it seems, is bigger than the iris itself. I. reichenbachii is a dwarf, ranging in height from 10 to 30 cm (4 to 12 inches), with one or sometimes two buds at the top of the stalk. (Very rarely, a third bud may appear further down the stalk.) The flowers are yellow (often with brownish markings or blending), smoky violet, or occasionally clear deep violet.

Iris reichenbachii

The species is native to the Balkan peninsula, from Rumania and Bulgaria through Serbia and into Greece. A related species, I. suaveolens, is similar but smaller. Two other species names, I. balkana and I. bosniaca, are now regarded as synonyms of I. reichenbachii.

As a garden subject, I. reichenbachii is pleasant enough, if somewhat unremarkable. It has found a home with rock gardeners and plant collectors. For those who fancy modern hybrid dwarf and median irises, this little species can seem drab by comparison. The petals are rather narrow, substance is lacking, and the colors can seem a bit murky.

To the hybridizer, however, I. reichenbachii has something unique to offer. Its chromosomes are very similar to those of tall bearded irises, and it is quite compatible with them. Furthermore, I. reichenbachii exists in both diploid (two sets of chromosomes) and tetraploid (four sets) forms. Since modern TBs and BBs are tetraploid, they can cross with tetraploid I. reichenbachii and produce fertile offspring. (For an explanation of diploids and tetraploids, see my earlier blog post Tetraploid Arils, Anyone?)

'Progenitor' (Cook, 1951)
 from I. reichenbachii X TB 'Shining Waters'

In the 1940s, the talented hybridizer Paul Cook did precisely that. A seedling from the cross, aptly named 'Progenitor', was registered in 1951. It was an unimpressive iris of intermediate size, but Cook could see its potential. 'Progenitor' was a bicolor, with violet falls and pure white standards. At the time, this was a new color pattern. (Earlier bicolors were actually variations on a "spot pattern" from I. variegata, and seldom showed the completely solid falls and pristine standards of 'Progenitor'. It is interesting to note that I. reichenbachii itself is not a bicolor. The bicolor pattern resulted from combining its genes with those of the TB parent. By crossing 'Progenitor' back to high-quality TBs, Cook was eventually able to transfer the bicolor pattern onto irises that otherwise showed no resemblance to the modest little dwarf that had given rise to the new pattern. 'Whole Cloth' (Cook, 1958), four generations on from 'Progenitor', won the Dykes Medal in 1962.

Virtually all TB and BB bicolors today (standards white, yellow, or pink; falls blue, violet, purple, reddish, or brown) are descendants of 'Progenitor', and hence of I. reichenbachii.

But there is still more to be done with this interesting little species. When Cook was making his crosses, there was very little interest in dwarf or median irises. In fact, medians as we know them today hardly existed at that time. So Cook simply worked to transfer the new color pattern into TBs. Today, however, there is considerable interest in breeding medians, especially BBs and MTBs that are consistently small and dainty. Surely the little dwarf I. reichenbachii has something to offer in these endeavors. The tetraploid forms are compatible with BBs and tetraploid MTBs, while the diploid I. reichenbachii could be crossed with diploid MTBs. Since these sorts of crosses should produce fertile seedlings, a hybridizer could continue the breeding line to achieve any desired goal.

Iris reichenbachii

I. reichenbachii is a little difficult to find in commerce, but not impossible. Some specialty nurseries list it, and if one is willing to grow from seed, it shows up rather often in seed exchanges that include iris species.

If you see this odd little species available somewhere, why not give it a try? Perhaps even make a cross or two to see what happens...

Arilbred medians: irises that have it all

by Tom Waters

'Brash and Bold' (Black, 2009)

In my blog post this April about arilbred irises, I mentioned that these striking garden jewels come in all sizes. Today I'm going to focus in on the smaller arilbreds, which are often called arilbred medians.

All arilbreds have in their ancestry both bearded irises and the exotic aril irises from the mountains and deserts of southwestern Asia. Because tall bearded irises have long been the most popular and extensively bred of the bearded types, it was mostly tall bearded irises that were used to produce arilbreds.

However, there have always been hybridizers of an adventurous bent who used dwarf or median bearded irises to produce arilbreds. Among the first irises from such breeding is 'Zwanenburg' introduced by French hybridizer Louis Denis in 1912. Its parentage is a matter of debate, but a dwarf bearded cultivar derived from Iris lutescens was one of the parents, and there is clearly aril ancestry as well. Remarkably, it is still being grown today! Its muted bronze and gray colors are not to everyone's liking, and the stalks and petals are rather flimsy, but it grows and blooms prolifically and has been delighting gardeners for over a century.

'Zwanenburg'

In the middle of the 20th century, two developments occurred that paved the way for renewed interest in arilbred medians. The first was the development of the modern standard dwarf bearded irises (SDBs) from TBs crossed with the tiny dwarf species Iris pumila (see my blog post in July of this year here). The second was the creation of a "fertile family" of arilbreds from TB and aril breeding. Most earlier arilbreds had been quite sterile, which meant that new ones could only be created by working with the pure arils themselves, which are difficult to grow and breed with. The new fertile arilbreds meant that it was now relatively easy to produce all sorts of new irises with aril ancestry.

Since that time, crossing SDBs with fertile arilbreds has been the most common way to create arilbred medians. They vary a lot in height, but average around 18 inches high. These are only 1/4 aril, so often their aril characteristics are rather subtle. The best have obvious veining or a definite signal patch below the beard, and have a more globular flower form than do the intermediate bearded irises (IBs), which they otherwise resemble.

'Octave' (Johnson, 2008)

'Enigmatic Elf' (Jensen, 2007)

'Suspect' (Johnson, 2006)

Some small arilbreds were also produced by crossing SDBs or dwarf species directly with pure arils. Because they bypass the TB ancestry that comes in when using an arilbred parent, they are both smaller (averaging around 10 inches) and more aril-like.

'Loudmouth' (Rich, 1970)

'Tiny Pirate' (Rich, 1990)

'Vera-Marina' (Ransom, 1998)

Most arilbred medians carry genes from three distinct types of irises: arils, tall bearded, and dwarf bearded (usually Iris pumila), making them one of the most genetically rich types of irises you can grow. They really do have it all! This genetic diversity expresses itself in a wide range of colors and patterns, a wide range in height and garden uses, and adaptability to a range of climates. Their dwarf ancestry helps many of them deal with cool rainy climates better than the taller arilbreds, and conversely their aril ancestry helps them do better in mild-winter climates than the SDBs.

Most arilbred medians are sterile, but there are a few fertile ones from unusual breeding approaches. 'Aladdin's Gem' (Thoolen, 2002) has only Iris pumila and pure arils in its ancestry - no TB heritage at all! Likewise, 'Anacrusis' (Mathes, 1992) is derived from pure arils and the dwarf bearded species Iris suaveolens. It has a number of worthy descendants, including the striking and popular 'Concerto Grosso' (Mathes, 1998), which won the C. G. White Medal in 2005.

'Aladdin's Gem'

'Anacrusis'

'Concerto Grosso'

Have you tried any arilbred medians in your own garden? How do they do in your climate?

Standard Dwarf Bearded Irises: A Success Story

by Tom Waters

'Abuzz With Charm' (Coleman, 2013)

Standard dwarf bearded irises (SDBs) are defined as bearded irises between 20 cm (8 inches) and 41 cm (16 inches) in height. But behind that simple definition is an exciting story of the creation and development of a family of wonderful garden plants unknown in nature, beginning with two curious hybridizers collaborating on an experiment and culminating in what would become an enormously successful class of irises, second in popularity only to the tall beardeds.

The story begins in the 1930s with Robert Schreiner seeking out seeds of the dwarf bearded species Iris pumila, native to eastern Europe. There were already dwarf irises grown in gardens at that time, nearly all of them derived from Iris lutescens, a species native to the western Mediterranean: Italy and southern France. There was not much potential in breeding these dwarfs, however. The color range was limited (yellow, violet, and occasionally off-white), and attempts to add more variety by crossing them with tall bearded irises produced only sterile intermediates, a dead end as far as improving the dwarfs was concerned.

Iris pumila

Iris pumila offered the prospect of something new for dwarf breeding. Although not grown in western Europe or North America, it was known to iris specialists. It was one of the iris species originally listed by Linnaeus, and was described in W. R. Dykes's The Genus Iris and other sources. It is a truly diminutive iris, virtually stemless, with the tip of the blooms often only 10 or 15 cm above the ground. Its range of colors is delightful: yellow, cream, pure white, violet, purple, and blue, almost always with a darker spot on the falls. Instead of just lamenting its unavailability from commercial sources, Schreiner initiated communication with plant enthusiasts in eastern Europe, and was eventually able to import some seeds of this promising species.

By the 1940s, Iris pumila was being grown by a small handful of iris hybridizers in the USA. Two of them, Paul Cook in Indiana and Geddes Douglas in Tennessee, decided to exchange pollen. Iris pumila was blooming in Indiana around the same time as the tall beardeds were blooming in Tennessee. The results of these crosses delighted them both. The stems grew about 30 cm in height, only slightly larger than the garden dwarfs of the time. There were two buds at the top of the stem, and often a third on a short branch. The flower form was perky and modern by the standards of the time, and the colors were bright and varied wonderfully. And, most extraordinarily, these new hybrids were fully fertile and could be bred with one another for as many generations as the hybridizer desired. These were the first of a new type of iris, now called SDBs. Paul Cook introduced the first three to the world in 1951: the clear yellow 'Baria', blue 'Fairy Flax', and white and green 'Green Spot', which achieved an enduring popularity among iris enthusiasts.

'Green Spot' (Cook, 1951)
photo: Barbara-Jean Jackson

The creation of these new hybrids soon caused controversy. Were they dwarfs or were they intermediates? Many dwarf enthusiasts insisted on the latter view. Iris pumila was a dwarf, after all, and crossing dwarfs with TBs was the classic recipe for intermediates. Furthermore, they argued, no true dwarf iris could have a branched stalk, which SDBs often did. Others, however, noticed that these new irises were much closer in size and general appearance to the dwarfs than to the intermediates, and preferred to just stretch the definition of "dwarf" a little bit to accommodate the new hybrids. Geddes Douglas thought they should be in a class by themselves, neither dwarf nor intermediate, and proposed calling them "lilliputs".

By the mid-1950s, those who preferred grouping the new irises with the dwarfs had prevailed. The AIS adopted a classification where any bearded iris up to 16 inches in height was considered a dwarf. The Dwarf Iris Society refused to accept this however, and the result was a schism between the two groups, with the DIS having its own judging standards and its own system of awards. This state of affairs was untenable, and by 1958, it was clear that the classification problem needed serious rethinking.

'Rain Dance' (B. Jones, 1979)

The final outcome was abandoning the simple division of dwarf, intermediate, and tall, and replacing it with four "median" classes in between the dwarfs and the talls. The intermediate class remained, but now there would also be a new class for "lilliputs" and two more classes in the intermediate height range, one for small TBs (border bearded) and one for the dainty diploid "table irises" (miniature tall bearded).

So the new pumila/TB hybrids now had their own class, but what should they be called? Douglas's name "lilliput" was deemed a bit too fanciful. The final decision was to call them "standard dwarf bearded" and refer to the smaller true dwarfs as "miniature dwarf bearded". The Dwarf Iris Society would continue to promote only the MDBs, while a new organization, the Median Iris Society, was created to promote the four median classes: SDB, IB, MTB, and BB. The result is a slightly perplexing situation where the SDBs, although having the word "dwarf" as part of their name, are technically medians, not dwarfs.

This brand new type of iris shook up the conventional thinking of the time, but the result was much better than if they had been forced into either the dwarf or intermediate categories. Having their own class and their own awards gave great encouragement to breeders striving to improve them. And the improvements came rapidly. Breeders like Bee Warburton and Bennett Jones were at work from the beginning, scarcely behind Cook and Douglas in producing new SDBs. Before long, most hybridizers were no longer crossing Iris pumila with TBs to produce new SDBs. It was easier to simply cross the existing SDBs with each other, and the results were usually better too.

The influence of the SDBs extended beyond their own class. Today, most IBs come from crossing SDBs with TBs, and most MDBs derive from SDBs as well.

SDB breeding produced some extraordinary surprises. It was originally thought that some of the recessive colors and patterns, such as pink and plicata, could only appear in TBs. But it did not take long before they began showing up in SDBs as well. Today's SDBs have virtually all the colors and patterns seen in TBs, as well as the "spot pattern" inherited from Iris pumila. I think it is fair to say they are the most varied class of irises in existence.

'Chubby Cheeks' (Black, 1985)
photo: Mid-America Garden

In the nearly 65 years since the first SDBs were introduced, there has been a steady improvement in form and substance. Bennett Jones's creamy white 'Cotton Blossom' was hailed as an early improvement in form, with wide round petals and light ruffling. But the greatest breakthrough was Paul Black's 'Chubby Cheeks' in 1985. A prodigious parent for decades, this iris and its descendants set a new standard of form for the entire class.

SDBs are deservedly popular, and not only for their varied colors and appealing flower form. They bloom about a month earlier than TBs in most climates, greatly extending the iris season. Furthermore, their size makes them more versatile in garden design than their larger cousins. They can be tucked in next to a doorway, along a path, or even used in small "postage stamp" backyards where TBs would be out of scale. It's hard to imagine the iris world without them.

And we owe their very existence too a few creative souls whose curiosity prompted them to step outside the status quo and try something different. Who can say where the next great iris success story will come from?