Miniature Dwarf Bearded Irises: A Starter Kit

By Tom Waters

This time of year, most gardeners in the northern hemisphere are patiently (or not) waiting for spring to come. If you are a bearded iris enthusiast like me, that probably means you are anticipating the earliest blooming of them all: the delightful miniature dwarfs. 

In the American Iris Society classification system, miniature dwarf bearded (MDB) include bearded irises up to 8 inches (20 cm) in height. Often overshadowed by their larger relations, the standard dwarf bearded (SDB), the MDBs nevertheless offer something special to the iris garden. Many of them bloom before the SDBs, when there is little else in flower. Their daintiness gives them an added charm: some iris enthusiasts are fascinated by tiny flowers and enjoy the surprise of encountering an unexpected bloom in some little corner of the garden. If you try growing an MDB, you'll be glad you did!

But how to get started? Many commercial growers only offer the larger bearded irises, and those that do sell MDBs may have just a few. With SDBs so outnumbering the MDBs, it can take a little extra effort and attention to seek out these tiny gems. In this post, I make a suggestion of a "baker's dozen" MDBs for someone looking to get started. This is not just a list of personal favorites; the irises in the list have been chosen because they represent the full range of the class, in terms of color, form, climate adaptability, genetic type, and historical era. This is important because not all MDBs are alike. Only by sampling a full range of types can you get a good feeling for what the class has to offer and discover your own preferences. All the irises on the list have been available commercially in recent years and are widely grown in gardens where MDBs are found. They should not be too difficult to obtain. 

In addition to the obligatory hybridizer and year, I have also included the ancestry type of each iris in the list. Type I MDBs come from SDB breeding, type II from crosses between SDBs and the species Iris pumila, and type III are pure I. pumila. For a basic introduction to these types, see my earlier blog post Dwarfs for Every Garden. For a more thorough, technical explanation, see my article The Miniature Dwarfs, which first appeared in the 2019 edition of the Dwarf Iris Society Portfolio.

‘Alpine Lake’ photographed by Tom Waters

'Alpine Lake' (A. and D. Willott 1981, type II) is a much-loved classic MDB with crystal white standards and falls with a pastel blue spot. Virus sometimes makes the falls a bit splotchy, depending on weather; but it is still one of the best.

‘Beetlejuice’ photographed by Tom Waters

'Beetlejuice' (P. Black 2013, type I) is a unique plicata with distinctive "whisker" lines on the falls. It sometimes sends up stalks that push the height limit of the class, but the compact shape of the flowers preserves its "dwarf" look.

‘Cinnamon Apples’ photographed by El Hutchison

'Cinnamon Apples' (P. Black 1990, type I), one of Paul Black's earlier creations, is notable for its rich reddish brown color in a class where blue, purple, yellow, and white tend to predominate.

‘Ditto’ photographed by Barbara-Jean Jackson

'Ditto' (B. Hager 1982, type I) is not only a delightful little iris with its cream color and bluish red spot, but it also reblooms in some climates.

‘Dollop of Cream’ photographed by Tom Waters

'Dollop of Cream' (P. Black 2006, type I) is a personal favorite. Earlier than most type I MDBs, it often ushers in the season here. I also appreciate the pastel color and the tasteful ruffling that is not too overdone.

‘Gecko Echo’ photographed by Jeanette Graham

'Gecko Echo' (B. Kasperek 2007, type I) is unmistakable for its deep mustardy fall spot.

‘Gold Canary’ photographed by Tom Waters

'Gold Canary' (A. and D. Willott 1981, type II) really lights up the garden in early spring. 

‘Hobbit’ photographed by Tom Waters

'Hobbit' (L. Miller 2004, type III), a tiny (4.5 inches!) blue pumila from Lynda Miller, is one of the best of this type.

‘Icon’ photographed by Tom Waters

'Icon' (Keppel 2008, type I) is a real zinger with its intense orange color and contrasting spot. Also an early bloomer here.

‘Little Drummer Boy’ photographed by Tom Waters

'Little Drummer Boy' (A. and D. Willott 1997, type III), a striking pumila with deep navy blue spots is an enduring favorite.

‘Royal Wonder photographed by Tom Waters

'Royal Wonder' (C. Coleman 2013, type III) is a robust, floriferous purple pumila - incredible impact for such a little iris.

‘Small Token’ photographed by Tom Waters

'Small Token' (L. Miller 2014, type II) is a rich and subtle red color on a very diminutive plant. Unique!

‘Zipper’ photographed by Jeannette Graham

'Zipper' (D. Sindt 1979, type II) is a standout with its deep yellow petals and electric violet beards. A true classic.

If you haven't tried the miniature dwarfs, I hope this "starter kit" gives you a good taste of what the class has to offer. If you already grow some, maybe this list will inspire you to pick up a few more and diversify your collection. Mine usually start blooming the last week of March here in northern New Mexico. I'm counting the weeks!

The Classic MDBs

 by  Tom Waters

The world of dwarf and median irises was revolutionized in the 1950s when Paul Cook and Geddes Douglas crossed the dwarf species Iris pumila with tall bearded irises (TBs) to create what became known as standard dwarf bearded irises (SDBs). The new SDBs were not only lovely, varied, and useful garden plants in their own right; but they were fertile parents, leading to all sorts of new avenues for hybridizers.

Hybridizers soon tried crossing the SDBs back to both of the parent types, TBs and I. pumila. Crossing SDBs with TBs produced a whole new style of intermediate bearded irises (IBs), whereas crossing SDBs with I. pumila produced a new style of miniature dwarf bearded irises (MDBs).

'Bee Wings'
photo: El Hutchison

By ancestry, these new MDBs were 1/4 TB and 3/4 I. pumila. From I. pumila, they inherit daintiness, earliness of bloom, and floriferousness. The TB ancestry lends them a greater variety of color and pattern, and a bit more width and polish in flower form. Dwarf breeders and growers were delighted with these creations; and they became quickly popular, all but replacing the earlier dwarfs from I. lutescens breeding in just a decade or so.

'Alpine Lake'
photo: Tom Waters

The first MDB from SDB x I. pumila breeding to win the Caparne-Welch award was Alta Brown's 'Bee Wings' (Brown, 1959), which won the award in 1963.  By 1990, six others from this type of cross won the award. Especially notable among them were 'Zipper' (Sindt, 1978), a deep yellow with a stunning blue-violet beard, and 'Alpine Lake' (Willott, 1980), a soft near-white with a diffuse blue spot. I refer to these as "classic" MDBs, because they set the standard for the class during this time of great progress and interest.

'Zipper'
photo: Jeanette Graham

Another popular type of MDB was produced by crossing SDBs with each other and selecting irises that were small enough to fall under the height limit of the MDB class (currently 8 inches). These had the advantage of showing all the color patterns of TBs, including plicata and tangerine pink. Although both types were popular, hybridizers breeding specifically for MDBs preferred the SDB x I. pumila cross, which produced a much greater proportion of early-blooming, MDB-sized seedlings.

After 1990, the SDB x I. pumila cross gradually fell out of fashion, with most of the new MDBs coming from SDB x SDB breeding. The reason for this is two-fold. First, the SDBs had been steadily progressing in color, pattern, and form; and the classic MDBs from SDB x I. pumila could not really keep up. Second, fewer breeders were breeding specifically for MDBs and growing I. pumila for that purpose. Most breeders were instead working with their established SDB lines, which sometimes produce MDB-sized plants "by accident," as it were. So the SDB x SDB cross would do double duty, producing both SDBs and MDBs.

'Wee Dragons'
photo: Jeanette Graham

Classic MDBs are still being produced, however. My favorite recent one is Lynda Miller's 'Wee Dragons' (Miller, 2017). The recent Caparne-Welch winner 'Kayla's Song' (D. Spoon, 2008) is of complicated ancestry, but its overall appearance makes it likely that it too is 3/4 I. pumila and belongs in this category.

Although it is clear that the MDBs from SDB x SDB breeding will continue to dominate the class with their modern form and exciting color patterns, the classics should not be completely forgotten. The advantages of early bloom and guaranteed dainty size in all gardens should not be set aside too quickly. And since this type of cross is not often made these days, we don't have a very full picture of its potential when modern SDBs are involved.

'Kayla's Song'
photo: Ginny Spoon

Although my own hybridizing interests are focused elsewhere, I make some SDB x I. pumila crosses each year and donate the seeds to the Dwarf Iris Society seed sale, in the hopes of encouraging interest in the classic MDB cross.

If you grow MDBs, keep your eye out for classic MDBs that have I. pumila or one of its cultivars as a parent. They will delight you with their early bloom and daintier looks. 

Dwarfs for Every Garden

by Tom Waters

The dwarf bearded irises (those classified as miniature dwarf bearded, or MDB) are a charming addition to any garden. With blooms held eight inches (20 cm) or less from the ground, they are the daintiest of all the bearded irises. They are also the earliest to bloom. In my garden, the first ones open a full two months before tall bearded season.

Almost all MDBs grown today fall into one of three categories. All three groups owe their existence to the eastern European species Iris pumila, which came to be used by American hybridizers in the 1940s.

'Liitle Drummer Boy'

The first category is Iris pumila itself. This tiny species is seldom more than 4 or 5 inches (10-12 cm) in height, with just one bloom per stem. (Actually, the stem is often almost nonexistent, most of the height being in the perianth tube formed by the flower parts themselves.) It comes in a range of colors from white and yellow to blue, violet, and purple, usually with a darker colored spot on the falls. There are a number of cultivars produced by hybridizers or selected from wild forms for their garden value. Some of my favorites are 'Little Drummer Boy' (Willott, 1997), 'Hobbit' (Miller, 2004), and 'Royal Wonder' (Coleman, 2013).

'Hobbit'

'Royal Wonder'

The next two categories came about as a consequence of the creation of the first standard dwarf bearded (SDB) irises in the 1950s. As I discussed in an earlier blog post, the SDBs were the result of crossing Iris pumila with tall bearded irises (TBs). The SDBs averaged about 12 inches (30 cm) in height and would typically have 2 or 3 buds. They are regarded as medians, not as true dwarfs, because of their larger size and occasional branch, something not seen in traditional dwarf irises.

'Alpine Lake'

Shortly after the SDBs appeared, hybridizers crossed them back to Iris pumila to produce irises of truly dwarf stature, but with a little something extra from their TB ancestry: plicata pattern, for example, or wider petals and more flaring form. These were the most common type of MDB in the 1960s, '70s, and '80s. 'Knick-Knack' (Greenlee, 1961), 'Zipper' (Sindt, 1979), and 'Alpine Lake' (Willott, 1981) are good examples of this type.

The third category came about from SDB breeding in an even more direct way. Sometimes crossing two SDBs produces an iris smaller than average. These small ones, if they are 8 inches or less in height, belong in the MDB class, since the definition for that class is based on height, not ancestry. Because so much work has been done to improve the SDB class over many decades, these are often the most "developed" dwarfs in terms of form and variety of color and pattern. Popular examples of this type are 'Dollop of Cream' (Black, 2006), 'Icon' (Keppel, 2008), and 'Beetlejuice' (Black, 2013).

'Dollop of Cream'

'Icon'

Generally speaking, the greater the amount of Iris pumila in a dwarf's makeup, the smaller, earlier, and more adapted to cold winters it will be. Those with less Iris pumila will have larger flowers with greater width and ruffling, a greater range of color patterns, and perform better in warm-winter areas.

There are no official designations for these categories, although hybridizers sometimes identify them by the number of chromosomes: Iris pumila has 32, the SDBs and their small MDB progeny have 40, and the SDB x pumila hybrids have 36.

How can you tell which of these categories and MDB belongs to? Alas, the only way to be sure is to look at the parentage on the Iris Encyclopedia or other resource. In most cases, this will lead you back either to SDBs or to Iris pumila, or else the parentage will be an SDB x pumila cross. If this sort of research interests you, my list of pure Iris pumila cultivars may help make sense of things.

I love dwarfs in all their variety, and happily live in a locale where all kinds grow well. Do you grow dwarfs in your own garden? Which kinds are your favorite?

Iris pumila: a Tiny Treasure

by Tom Waters

Iris pumila

In an earlier blog post, I wrote about how the tiny bearded iris species Iris pumila was imported to the US by Robert Schreiner in the 1930s and crossed with the popular tall bearded irises, giving rise to a whole new type of garden irises, the standard dwarfs (SDBs).

Today, I thought I would write about Iris pumila itself. Besides being an extraordinary find for iris hybridizers, it is a delightfully varied species that makes a wonderful garden plant. It is invariably the first bearded iris to bloom in the spring, starting several weeks before most of the hybrid dwarf cultivars.

In the wild, Iris pumila grows in a wide range across eastern Europe, from Austria in the west through Hungary, Romania, Ukraine, and into the Caucasus Mountains as far as Armenia and even Turkey. It is often found at higher elevations and dry, continental steppe climates. It is adapted to cold winters and sunny, open spaces. Conventional wisdom has it that Iris pumila does best in areas of colder climate (USDA hardiness zone 6 or colder), although I have grown it in southern New Mexico (zone 8), so it may be worth a try even in warmer areas.

Iris pumila is among the tiniest of bearded irises, with the tip of the blooms only about 10 cm from the ground. Usually, the stem is so short as to be hardly detectable; the blooms are held aloft on an elongated perianth tube, so that each bloom seems to be just sitting atop the rhizome from which it grows.

The species shows a phenomenal range of color. To judge from pictures I have seen on the internet, Ukraine seems to be the center of its diversity, with many extraordinary color combinations seldom seen in plants that have been imported to the US or western Europe.

The basic color may be blue, purple, yellow, or white, in any shade from pale to intensely saturated. There is almost always a darker "spot pattern" on the falls, which may be small or may cover virtually the entire petal. The spot may be solid color, or appear as rays or veins or an uneven wash of color.

You can find Iris pumila offered for sale by some alpine or rock garden nurseries. (A word of caution: non-specialist nurseries, like garden centers, often use "Iris pumila" to label any small bearded iris cultivar; these are not the true species.) Many seed exchanges have it, and growing from seed can be extraordinarily fun, since every seedling is different. It does take some patience, however, as irises take 2 to 3 years to bloom from seed.

There are also named cultivars of Iris pumila available from specialty iris growers. Many of these are registered as miniature dwarf bearded (MDB), since they meet the definition of the class. More recently, some have been registered as species (SPEC). One very popular Iris pumila cultivar is 'Little Drummer Boy' (Willott, 1997), which won the Caparne-Welch Medal for best MDB in 2005.

'Little Drummer Boy' (Willott, 1997)

Some newer Iris pumila cultivars include 'Steppe' (J. Burton, 2011), 'Keystone Oracle' (Jesberger, 2011), 'Wild Whispers' (Coleman, 2012), and 'Royal Wonder' (Coleman, 2013). 'Keystone Oracle' is notable for turquoise tones around the beard and spot, which varies from dark to pale depending on climate.

'Keystone Oracle' (Jesberger, 2011)

'Hobbit' (Miller, 2004)

'Royal Wonder' (Coleman, 2013)

I hope I've given you a taste of the beauty and variety of this diminutive iris species. Have you tried growing any Iris pumila in your own garden?