The adjectives miniature, dwarf, and low growing used to describe iris mean different things to irisarians, botanists, and gardeners. In fact, only in recent years have clear-cut distinctions been made and adopted by the American Iris Society.
To home gardeners interested in iris for border edgings, rock gardens, and pots of spring color, the names of species and varieties suitable for such garden uses are more important than the fine points of classification.
In this article, therefore, I will discuss an iris that grows only about 6″ to 8″ inches tall, and that is good for such garden uses under the general heading “low growing,” regardless of whether they are considered miniature, dwarf, or low growers by the experts.
Some flower early in spring, others in mid or late spring, and bring color to gardens for about six to eight weeks.
Four Types Of Iris
Four types of iris are included:
- Bearded
- Beardless
- Crested
- Bulbous
For those who are interested, the characteristics of these divisions of the iris family, like the distinctions between low-growing types, are explained in most books that deal exclusively with iris.
Home gardeners should look under each of these headings in the colorful iris catalogs, where the species and varieties mentioned here, plus new hybrids too numerous to mention, will be found.
Bearded
Any sunny, well-drained location is suitable for them. In two or three years, a single plant will form a large clump that will be covered with flowers for several weeks.
They usually come into bloom just ahead of primroses and daffodils, flowering with them for a short period.
They like lots of sun, doing well along the edge of an open border and at the top of sunny walls. However, do not allow them to become crowded by other low-growing plants, like sedums or candytuft, or to be shaded by taller plants behind them.
Large clumps may be divided any time after bloom, but not later than mid-September in areas where winter is early, arriving about mid-November.
Here are a few choices named varieties to look for in the catalogs:
- Bouquet, dainty white and heliotrope, 6” inches
- Ink-Spot, showy bright blue-black, 6” inches
- Keepsake, tiny golden yellow with a bright orange beard, 4” inches
- Mist o’Pink, unique deep rosy mauve, 3” to 4” inches
- Sass Purple, rich dark velvety purple, 6” inches
- Tampa, probably the finest red, 6” inches
- Lemon Frost, light lemon-yellow, 6” inches
- Fairy Charm, lavender-blue and blue, 5” inches
- Teddy Bear, a late-flowering blend of light olive, violet, and olive brown, 6” inches
In addition, there is a species, I. arenaria, which is worth special attention. It is the tiniest of the bearded iris, a bright yellow, just 3” inches tall.
Beardless
Their cultural requirements are similar to those of the low-growing bearded iris with this exception: they appreciate slightly acid soil.
The species I. Verna is noteworthy because its mid-May dark lavender flowers have a distinct, deep golden line. Its foliage sometimes grows 8” inches tall, with the flowers held on 4-inch stems.
Crested
I. cristata will take sun or part shade, preferring a location shaded in the afternoon, and it needs soil rich in humus. Its flowers are light blue with a gold crest.
In my garden, it grows only 4” inches tall, but in other gardens, it may reach 9” inches in height. There is a white variety that is rare and not as hardy as the species.
Bulbous
As I write this in late January, two pots of the low-growing bulbous iris are in bloom on our sheltered south patio.
I. reticulata Violet Beauty always flowers in early spring, but this year, deceived by our mild January, it has bloomed for ten days.
The other, oxford-blue I. histrioides major, came into bloom on January 20. It is fairly rare, but you will find it not hard to grow.
By and large, bulbous iris, whether low growers or the tall Dutch, English, and Spanish types, do better in the Pacific Northwest, where I garden than in the East or Midwest.
But even here, we must allow them to dry out in the summer, and therefore pot culture is, I find, the most satisfactory way to grow them.
After their flowering period is over, the pots are lifted from the garden and placed in an area protected from the rain where they can dry out.
Then when fall rains come, they are repotted in fresh soil and returned to their garden locations. Finally, the pots are sunk into the ground to their rims.
Iris Reticulata
Iris reticulata is called “fragrant iris”—its deep violet-blue flowers, with conspicuous golden-yellow blotches on the lower petals, have the scent of sweet violets.
It grows 4” to 8” inches tall and is durable enough for naturalizing—even in the East—and I do not find it necessary to grow it in pots.
Reticulata named varieties to include:
- Cantab, dainty light blue with orange markings, 5” inches
- Harmony, pansy-blue, the small yellow central ridge on the blade of falls
- Hercules, rich bronze-toned violet with orange crest, 4” to 8” inches
- J. S. Dijt, glowing red-purple, scented, 4” inches
- Joyce is a uniform clear blue with an orange central ridge on the blade of the falls. It is a hybrid between the species reticulata and histrioides listed below
Iris Danfordiae
I. danfordiae is a bright canary-yellow shading into greenish yellow at the base of the segments. It sometimes flowers as early as late January and grows 3” inches tall.
Iris Histrioides
I. histrioides major is oxford blue and grows 6” to 8” inches tall.
Iris Virtani
I. vartani has a slate-gray to white flower, veined with soft blue and violet, and a yellow crest. Rather difficult to grow, it must be protected from too much rain. It is only 6” inches in height.
Iris Tuberosa
Special mention must be made of I. tuberosa, a tuberous type, as its name indicates. It is often listed as a distinct genus in the iris family. If you don’t find it under iris in catalogs or reference books, look for it as Hermodactylus tuberosus.
Its common name is snake’s-head iris, and the curiously shaped flowers are apple-green with velvety purple-black splotches on the falls. It grows 6” inches tall in my garden, although it is listed as 1’ foot or more by some reference books.
44659 by Marguerite Norris Davis