From the orient have come some of our loveliest garden flowers. The exotic Japanese iris is one of them.
It is a valuable addition to any garden, large or small, not only for its big, iridescent, saucer-shaped flowers.
It blooms at just the right time to bridge the gap between the roses delphinium-Madonna lily display in June and the midsummer spectacle of brilliant phlox.
The wide, flat blossoms with wavy-edged perianths of crepe-paper texture are perfectly designed to make the most of their gorgeous color: pink, lavender, mahogany-red, blue, purple, and white plus every imaginable blending of those hues.
As if that were not enough, the flowers are embellished with all sorts of mottlings, stipplings, and stripings, commonly with a dash of gold at their centers.
Borne on slender yet strong stems from 2’ to 3’ feet tall, they are excellent for cutting. And the graceful, grass-like foliage about 2’ feet high is a garden decoration in itself.
The Best Place To Plant Japanese Irises
The very best situation for Japanese irises is at the edge of a quiet stream or pool where they will be reflected in the water and will find growing conditions much to their liking.
They are also admirable in borders as single clumps, in groups of three to five plants, or in masses of one or many colors, depending upon the area and scale of a garden.
For increased interest and variation in texture, try interplanting them with shasta daisies, which bloom in the same season. The shastras, too, are good for cutting.
Japanese Design Of Planting
Although they usually look most at home in a naturalistic arrangement, someday, I hope to test my concept of Japanese design by planting just one clump of an outstanding variety, such as the following:
- ‘Gold Bound’
- Delft Blue’
- `Pyramid’
In a miniature beach of golden sand beside a small, shallow, irregularly shaped pool of still water.
I shall try to find some dark sand for the bottom of the pool to make it a mirror for flowers, sky, and clouds.
Their Requirements
The culture of Japanese irises, while not quite so simple as that of the spring-flowering bearded iris, presents no problem that any conscientious gardener cannot easily handle.
The plants like rich soil, which is very moist during spring and early summer, but dry at other seasons and slightly acidic (from pH 5.5 to 6.5).
Mix plenty of humus into the ground before planting for excellent growth and bloom. It will hold the moisture the plants need during their most active growth period.
If you use leaf mold from beneath pines or oaks, you’ll supply the proper degree of acidity.
If you use compost (prepared without lime) or partially decomposed, strawy manure, mix it in a little cottonseed meal for its acidifying effect.
Early Spring Planting
Japanese irises may be planted in early spring and should always be in the colder sections of our area or during September and early October.
After fall planting, and also in succeeding falls in cold sections where the winter covering of snow is not reliable as a mulch, the plants should be lightly covered with salt hay, straw, or dry leaves as soon as the ground freezes.
Pine needles make splendid mulch. Never cut off the old foliage until about time for new growth to start in spring.
Lifting Iris Clumps
Although the plants bloom best in full sun, they tolerate light shade. They should be lifted and divided every four or five years or whenever the centers of the clumps show signs of deterioration and the flowers begin to diminish in size.
Lift each clump and separate the roots. Discard the old, worn-out central portion of the clump, replanting only the strong, youthful divisions from the outer edge.
Set them 18” to 24” inches apart with their crowns (where the leaves start) flush with the ground, or a wee bit below it to allow for the soil’s settling.
A 3-inch potful of balanced organic fertilizer scratched into the soil around each plant annually after flowering ceases in July is all the necessary supplementary feeding.
Japanese Iris Seedlings
Unlike many hybrid perennials raised from seed, Japanese iris seedlings are worth growing.
The seed should be sown as soon as it ripens. The resulting plants will bloom in their second season.
Timely Watering
The moisture requirements of the Japanese iris are rather interesting. From the time the plants begin growing in spring until they are in bloom, they need a lot of water and almost swampy conditions.
Usually, nature supplies water adequately in early spring. But during late May and June, there may be dry spells when you want to keep the ground full of moisture – just short of actual sogginess – by artificial watering.
Hoe up a little earthen dike around the plants and fill the area inside it with water every afternoon or evening.
If you do your gardening in a limestone region, where there is likely to be considerable calcium in the water supply, try to collect and save a barrel of rainwater for this purpose.
As the flower buds open, they gradually taper off on the watering. From the end of their flowering season, until growth begins the following spring again, the plants appreciate dry soil.
Varieties Of Japanese Iris
Although there are a great many named varieties of Japanese iris on the market today, not many nurseries offer more than a few of them.
Those listed below are both handsome and popular enough to be generally obtainable.
Because practically every Japanese iris has a more or less golden color in the centers of its flowers, that fact is omitted from the following descriptions for the sake of brevity.
- `Gold Bound‘ – Pure white perianth banded in gold with a creamy white center. Tall, with large flowers of excellent substance.
- `Delft Blue’ – Late blooming beauty with very large blossoms of glorious blue-veined in a deeper shade with very dark centers.
- `Pyramid‘ – Immense flowers of deep violet-blue with white centers and veining.
- A typical “double” Japanese iris flower shows extra petals and gold markings in the center.
Anybody just beginning to grow Japanese irises will find it satisfactory to buy plants by color or, for a planting of many sizes, in a mixture of colors.
Sold At A Cheaper Price
Plants sold in those ways are cheaper than named varieties, although the latter is not expensive by modern standards.
You should not have to pay over a dollar apiece for any of the varieties in the previous list except ‘Delft Blue,’ which is new.
One of the loveliest mixtures, if I may call it that, is the new Marhigo strain embracing a broad and brilliant range of colors and patterns.
These Japanese beauties belong to the beardless or Apogon class of iris, including the Siberian iris, Iris sibirica, and our naturalized yellow flag, Iris pseudacorus.
Horticultural Japanese Iris Varieties
The Japanese iris is usually classified as Iris kaempferi, in the horticultural varieties we grow in our gardens, developed during centuries of loving culture in Japan.
There are probably some descended directly from the similar Iris laevigata and undoubtedly many whose lineage, if it could be traced, would include both species.
In their native habitats, the flowers of Iris kaempferi are reddish purple, while those of Iris laevigata are bluish purple.
Among the cultivated forms, there are both “single” flowering varieties with only six-part perianths and “doubles,” in which the styles have assumed the appearance of three smaller petals at the centers of the flowers.
However, the difference in appearance between “single” and “double” Japanese iris flowers is relatively minor, nothing like that between single and double roses or peonies.
44659 by S Henderson