I became interested in irises as teenager. After a year or
so of growing tall bearded irises, I became more aware of the other types available, and of the special groups of enthusiasts who had gathered
around each type. When I discovered that there was a group (
SIGNA) just for
“species iris”, I was baffled. In my biology classes at school, I had learned
that the species was the basic category for classifying all life on earth. So
didn’t all irises belong to some species or other? It didn’t make sense that
there would be a special iris society just for species.
Beginning classes in school, naturally, emphasize simplified
basic concepts at the expense of all the qualifications, complications, and
exceptions that the real world has to offer. In school I learned that two
individual animals or plants belong to the same species if they can breed and
produce fertile offspring. But that’s not always the case, especially in the
plant kingdom. Irises belonging to two different species can often cross and
produce fertile offspring, and in fact this is how most of our named garden
varieties of iris originated. Those named varieties (“cultivar” is the precise
term) are almost all hybrids, with two (or more, usually) different species in
their ancestry.
So now it started to make sense. People interested in
“species irises” were interested in the original iris species that exist in
nature, as opposed to the many garden cultivars that had been produced by
hybridizing, crossing different species with one another.
 |
| Iris paradoxa, an aril species from northeastern Turkey |
 |
| Iris paradoxa, an aril species from northeastern Turkey |
I grow bearded and aril iris species, because I’m interested
in hybridizing with them, and also because they come from parts of the world
with climate similar to my own, so it seems a good fit. Many people grow other
kinds of species: Siberians, Louisianas, and wild irises from North America,
Europe, and Asia.
 |
| Iris reichenbachii, a bearded species native to the Balkans |
 |
| Iris reichenbachii, a bearded species native to the Balkans |
 |
| Iris reichenbachii, a bearded species native to the Balkans |
What is the appeal of species irises for gardeners?
Obviously, botanists are scientifically interested in the original species,
which are the product of natural evolution and occupy distinct ecological
niches. For a gardener or iris hobbyist, this scientific curiosity can inspire
interest in the wild species. But there are other lures as well. There are many
species that have been used infrequently or not at all in hybridizing. If you
take a fancy to these, you will necessarily be growing species. Some of us like
the “wild look” as an alternative to the deliberately “altered” creations of
human hybridizers. And some like the idea of growing the wild irises native to
their own area. For others, conversely,
species from other parts of the world provide a connection with the plant life
of distant lands and environments.
 |
| Iris stolonifera, an aril species from central Asia |
 |
| Iris stolonifera, an aril species from central Asia |
 |
| Iris stolonifera, an aril species from central Asia |
If you take an interest in species irises, you soon learn an
important difference between species and hybrid cultivars. The hybrid cultivars
are all propagated by division. Each plant is an identical replica of the
original. Each one is really an individual organism, as distinct from all other
irises as you or I are from all other people. But a species is not an individual.
A species is an entire population of related individuals; it is like the whole
of Homo sapiens from all the places
humans live, with all their different characteristics and genetic heritage. So
whereas I can “have” a particular cultivar, say ‘Dividing Line’, in my garden,
I cannot “have” a species, such as Iris
pumila. I can only have at most a few individual plants that belong to that
species. They will all be different individuals, and all different from the
great numbers of other Iris pumila plants growing wild in
Eastern Europe.
Species enthusiasts embrace this fact, and often strive to
have a range of different plants representing each of the species they grow.
This not only adds interest to the collection, but helps preserve some of the
genetic diversity of the species in our gardens. Like many wild plants, irises
are often threatened in their native environment by human activity and
encroachment. The gardener who grows species contributes, in a small but
potentially significant way, to their conservation and preservation.
For those of us interested in hybridizing, growing many
different plants of the same species offers another benefit: genetic
diversity. If you trace the ancestry of
our garden hybrids back far enough, you will find the same ancestors appearing
over and over again. Despite all the range of color and form in the modern
hybrids, they actually come from a rather inbred gene pool. Going back to the
species expands the genetic base for our hybridizing efforts.
 |
| Iris pumila, a bearded species from eastern Europe |
 |
| Iris pumila, a bearded species from eastern Europe |
 |
| Iris pumila, a bearded species from eastern Europe |
This brings me to a final observation. One can obtain species
plants from commercial sources and others who grow them, including named
cultivars in some cases (these are selected individuals of the species, not
hybrids between different species). But it can be even more satisfying to raise
species from seed. Many iris societies and rock garden societies have seed
exchanges, where one can inexpensively obtain seed of many different iris
species, including sometimes seed collected in the wild. There are also some
commercial sources, mostly specialist plant collectors. When you raise irises
from seed, you will naturally be “selecting” those plants with the genetic predisposition
to do well in your own climate.
Growing species irises, particularly growing them from seed,
provides a window onto the natural world that growing only hybrid cultivars
cannot. There is a special pleasure that comes from raising these lovely
wildflowers, knowing that you are enjoying (and helping preserve) some of the
world’s beautiful and fascinating flora.
 |
| Iris missouriensis growing wild near my home in northern New Mexico |
