Little wonder that a plant so boldly decorative in outline and bearing a flower of exquisite coloring so marvelously formed should make its strongest appeal to the artistic Japanese. From these foremost gardeners of the world has come a strain of irises that neither orchids nor lilies can rival in beauty of form, texture, coloring, markings, and general effectiveness. In the Mikado’s garden, under ideal cultural conditions – that is to say, in rich, warm, sunny, alluvial land – the blossoms will measure from nine to twelve inches across their flat petals. Around the shores of those miniature lakes and streams in which the Japanese gardener, however humble, delights, the irises are no less lovely because a small garden demands that they be of lesser size. Every one appreciates the iris in Japan. Therefore, on the most costly cloisonné and ceramic, as well as on “many a vase and jar, on many a screen and fan,” whose decorator may receive only an eighth of a cent for his sketchy painting, this flower, imperial and democratic, is the most familiar. For the artist, at least, its value is double that of the national chrysanthemum.
Yet the Iris Kaempheri may be as easily grown as the potato. Moreover, it is perfectly hardy. High, dry lands do not suit its moisture-loving roots, but good garden soil, enriched with thoroughly decayed manure, deeply dug in and well watered during May and June – the blossom months in the northeastern United States – will produce flowers of wonderful size. Do not select a shady place for your irises. They thrive under full exposure to the sun, but moisture they must have to bloom their best, and sometimes their roots will penetrate two feet deep to get it. Naturalized in the water garden, where the tall, narrow, blade-like leaves rise in phalanxes around the shore and the stately beauty of the flowers is reflected in the mirror below, they are ideally situated; but let no one forego the delight of growing Japanese irises merely because he has not a pond or stream on his place. Some exceedingly fine specimens have been produced in a city back yard.
Now that the Occidental as. well as the Oriental hybridizers produce an enormous number of seedlings every year, new varieties are constantly offered in the catalogues – so many that, were their charms described in Japanese, they could scarcely be more bewildering to the American amateur. The original parents of Kaempfei’s lovely tribe were I. laevigata with drooping “petals,” modeled on the natural rule-of-three plan, and I. setosa with broader, more horizontal “petals,” the three outer and the three inner ones being of equal size in many of its new varieties, giving a strange regular symmetry to the flower. The pernicious trick of doubling and multiplying “petals” – a common vice of the up-to-date sport – quite destroys the iris’s natural grace of outline, which is its chief characteristic and charm. Blotches and patches of color like a circus pony’s sadly detract from its stately dignity. Surely the range of pure colors, from silvery white, through pale blue, lilac, plum, and purples, with exquisite veinings and star-like centers of contrasting shades or of gold, should satisfy the most exacting eye.
German irises differ from the Japanese in having shorter, broader, blade-like leaves and flowers not yet induced to lie flat, having three strongly recurved and handsomely marked “petals” or falls and three upright standards. Both kinds have creeping stems, and it is by division of these fleshy, thonglike roots that the plants are most successfully propagated. Set out early in the autumn, they should bloom the following May. It takes at least three years to produce flowers from seed – an interesting experiment for the amateur hybridizer, but one rarely tried except by commercial men. While not so impressively magnificent as the Japanese strain, the German irises are nevertheless very beautiful; their coloring including white, yellow, lilac, and purple – either one of which every iris would be in a state of nature – and, in addition, some queer browns and rich velvety maroons combined with yellows which are unusual and effective.
We hear of the common blue flag. In reality it is not a blue, but a purple. Yet there is a little dwarf iris, a variety of the Crimean Iris pumila and I. Persica, which are true blue – that heavenly color all too rare in our gardens.
No plants are of easier culture than the German irises. They like a dry soil, rich food, a sunny, open situation, and plenty of room to spread, but they do not insist upon any of these conditions. Neglect them, starve them, crowd them among the shrubbery, stifle them in the herbaceous border, bury them in the rock garden, still they will bloom – sulkily, perhaps, but far more than they really ought, considering. Give them a rich dinner once a year, and let them alone thereafter, they will repay you most lavishly. Just as the gorgeous pageant of Dutch bulbs – jonquils, narcissi, and tulips – passes, the German irises begin their royal show, several weeks before their Japanese sisters unfurl their banners. Special emphasis should be laid upon letting all irises alone. They resent being fussed over. If it is necessary to divide a clump, cut it in half with a sharp spade and fill in the hole with old, well-rotted manure. Don’t disturb the entire clump in order to take away part of it, and don’t bury the rhizome when you plant the root.
On the streets of London and Paris and in the market – places of western Europe are sold bushels of the very beautiful Spanish irises, whose charms are not yet appreciated here as they deserve to be. In loose, friable garden soil, in a sheltered corner, they yield a lovely crop of flowers to cut for the house. More dainty than the larger German and Japanese irises, they are airily poised like butterflies on the tip of tall, slender, swaying stems amid narrow, grasslike blades. Secure a ribbon of soft lead from your plumber, place it in the bottom of a bowl, pinch it about the iris stems, and so arrange a few that they appear to be growing out of the water. Pebbles conceal the lead and help the illusion. From the Japanese we are slowly learning not to bunch a miscellaneous lot of cut flowers in wads for our vases, but to give each flower its natural, characteristic attitude and isolation.
English irises, another group of these endlessly beautiful plants, grow from bulbs like the Spanish strain, but in form and poise the flowers more closely resemble the Japanese. Coming toward the end of the iris season, which they prolong until the hot weather, they are especially desirable for those who tarry too long in the cities to enjoy the spring flowers about their summer cottages. Bulbous irises suffer from moisture and bleak exposure. A dry soil, even clear sand at the base of the bulbs, preserves them from decay, and, while they must be well nourished if they are not to fail utterly, let no manure come in direct contact with these. The rhizomatous irises are the gross feeders.
Certain irises there are that should be in every garden. No one is too poor or too inexperienced to have at least one fine clump of Japanese or German irises; for instance, the early grayish-white Florentine “orris” (whose dried root furnishes the sachet of commerce), with its large grayish white flowers, often six inches deep, the falls veined with yellow and green at the base with an orange-yellow beard; or I. variegata, with large, slightly scented flowers, their standards bright yellow, their falls claret-red heavily veined. The yellow flag of England, I. pseudacorus, is delightfully decorative, and cheap enough to naturalize in quantities with our own native species where one is so fortunate as to own a stream. [Note: now known to be an invasive plant, I. pseudacorus should never be planted near wild waterways. – Mike] In similar situations, or even in ditches, the small but showy Siberian flag in blue, white and purple varieties is a charmer. And now that irises are being so successfully forced in the greenhouses, there is not a month in the year when we may not have them in our homes.