Color range and long flowering make irises one of the American gardens’ most important landscape materials.
In most parts of the country, a wise selection of growing iris will give continuous bloom from mid-March through October.
The earliest species, planted in drifts in sheltered, well-fed, well-drained nooks, provide a delightful spring picture.
Earliest Iris Species
Among them are the six-inch I. reticulata with rich purple, yellow-throated petals and spike-like foliage, and the tiny bright yellow I. danfordiae.
The latter does not always take kindly to our gardens, but it is worth trying because of its charming diminutive form.
Plant both with spring bulbs— crocus, scillas, snowdrops, and grape hyacinths (Muscari).
Set among primroses, rock cress (Arabis), and the pale yellow Basket-of-Gold (Alyssum citrinum), the ripening iris leaves will be hidden by a floral mass.
Dwarf Iris
Dwarf iris (I. pumila), a plant 10” inches to 2’ feet tall, is most useful in the sunny rock garden fronting taller perennials.
Hyacinth Orange Bovern and cobalt blue pulmonaria arc lovely with early fragrant white 6-inch iris, the Bride.
The main flowering season is from May to mid-July. Not only will the garden be most colorful, but the glaucous, sword-like foliage will lend strength and contrast.
Tall Bearded Iris
Especially good textured varieties make impressive and exquisite pictures. Though tall bearded iris is among the showiest, in small moist areas our native dwarf soft blue L cristata blooms happily among ferns and violets.
Siberian Iris
The dependable Siberian iris (I. sibirica) grows anywhere, but given ideal moisture and semi-shade, it does especially well. Plant it along streams, ponds, or in the wet spots of a flower bed.
Perry’s Blue
Perry’s Blue, a favorite sky-blue, Caesar’s Brother and Kingfisher, both deep violet purples, Snow Queen and Snow Crest, good whites are lovely against a dark background with Hemerocallis (lava, or in front of Japanese maples.
I. fulva, similar to the Siberian, except for its unusual copper-colored flowers, likes sun, and though not always hardy, if it blooms but a season— well done!
Roof Iris Of China
The graceful 12-18 inch I. tectorum, sometimes called the roof iris of China, because it grows on thatching, resembles the large lavender blue Japanese kinds.
The light green leaves grow in a fan-shaped stalk, a good border plant for highlights and texture.
The varieties Lord Wolseley and Ochroleuca of I. spuria and I. pseudacorus (yellow) are tall and like sunny, moist spots. Sometimes Ochroleuca fails to bloom, but its tall foliage adds a welcome line.
Japanese Iris
The Japanese iris (I. kaempferi) is the aristocrat of the garden, blooming from late June until mid-July. The impressively large flat flowers vary from whites through all shades and tints of blues, lavenders, purples, and wine-red, but there are no yellows.
Unlike bearded iris, the Japanese prefer wet feet and acid soil, sun, and no manure. Give them plenty of water as the buds show.
Japanese iris may remain in the garden for 40 years and are worth any extra trouble. Large masses are truly regal.
Some intermediate types will bloom again in the fall. I. dichotoma which flowers in August, is sometimes treated as an interesting but not showy annual.
Pleasing Color Combinations
There are wide new varieties of tall bearded iris. The following color combinations are pleasing. A group near a blue spruce suggests a cool picture.
Use 48-inch Great Lakes, a rich, clear blue self with handsome foliage, 36-inch Sylvia Murray, huge flowers of lupine blue with white peonies, Phlox divaricata, and I. tectorum for overlapping bloom.
The long-lasting iris Mulberry Rose, The Admiral of deep intense blue, Minnie Colquitt, a large white plicata with wine-purple stitching along the falls, bordered with Dianthus plumarius, makes a warm picture.
With 36-inch iris Chantilly, a ruffled soft pink and Black Ruby, with pink lupine and mixed aquilegias.
The early Lady Mohr, with white oyster standards, pale greenish falls, Thotmes III, golden tan, and Pinnacle, large primrose yellow bicolor with a red Japanese maple background, is an interesting color combination.
Scotch broom or Harison’s Yellow rose makes an interesting dry spot companion for 40-inch New Snow, a sturdy ruffled white with Ola Kala deep orange-yellow, and Argus Pheasant of rich reddish-brown.
Syringa josikaea having soft mauve-pink flowers, is a desirable background for pink irises, such as Pink Sensation and Blue Shimmer, a lovely medium blue plicata, planted with pink and lavender aquilegias.
The salmon-pink Mrs. Perry oriental poppy massed with the Capital, a clear white, Happy Birthday, a flamingo pink, and Linum perenne is a striking combination.
The mahogany-red hemerocallis Rajah in front of Neuvo Laredo, Bryce Canyon, and Firecracker plicata, all of the similar shades and good form lightened with creamy yellow Amandine is an exciting combination.
Yellows and oranges of calendulacea azaleas are striking with Helen McGregor, one of the best beautiful, clear pale blue, Blue Rhythm large cornflower blue, Melody Lane apricot, and Sable almost black. Face these with Scilla campanulata, blue pansies, and Nepeta mussinii.
Avoid too many kinds and colors of iris in small gardens. A few good varieties repeated will be more pleasing and restful to the eye.
Designing With Iris
In making a design, bear in mind that blues are important for a feeling of distance and peace, next to the pale yellows and creams, and grays. Whites are accent points.
Designing with an iris is more than just planting another perennial. It is more like creating a beautiful stained glass window.
Everything is at hand—color, form, and material. It is up to the gardener to create a memorable design.
44659 by Mary Louise Johnson