Pacific Coast Iris

Irises are the rainbow bridge between the sky, the land and I. Pacific Coast Irises form the rootstock foundation of my long-term appreciation for the richness and diversity found in west coast wild flowers. They are primarily the children of three species and of hybrids between. Iris douglasiana is easily grown and was named after David Douglas, an early botanical explorer. His namesake is the lifeblood of many hybrids, and grows abundantly along the coast from Santa Barbara to Oregon. I. douglasiana foliage is handsome and evergreen. Dark green and shiny on the surface. It carries showy, orchid-like blooms that appear in spring and range from white to lavender or violet. Hybridization has lengthened the season of blooms, as well as the wellspring of colors. "Canyon Snow" is an outstanding selection by Dara Emery of Santa Barbara Botanic Gardens, with broad, exceptionally shiny leaves and branching stems of large pure white blossoms with yellow markings. Height for this species is variable, but can be up to thirty inches. Douglasiana Irises prefer sun or part shade, with little summer watering.

Iris innominata despite its (no name) description is perhaps the most welcome iris discovery of the depression 1930's, made in the Siskyous by Mrs. John R. Leach a well-known Portland botanist. With its brilliant gold, it lent new excitement to iris gardeners and hybridizers alike. White and purple forms also exist and where the colors overlap, exiting bi color variations are found. "Burnt Umber" is a hybrid of burnt golden-yellow flowers with maroon-brown veining and dark gold throats. Proper drainage is a must for this species (or hybrids involving this parentage). Partial shade is preferable. The species Iris tenax brings the Pacific Coast Iris to the northern limit of its range. Tenax refers to the toughness of the plant, and like douglasiana, its fibers were used by the native people in the making of ropes, fishing nets and snares. The very edges of the leaves were separated by thumbnail into fine silk-like strands, and then laboriously woven together. The resulting rope was strong and pliable enough to catch deer, hence it was known as deer rope. This iris is found in prairies and open coniferous or oak forests from south-central Washington to northwest California. Gene hardiness born in plants that grow from the coast into the Cascade range up to 3,500 to 4,000 feet (an environment where daytime spring temperatures can fluctuate by 50.F). On I-5, near Chehalis, WA. a clear violet-blue group was brilliantly visible every spring. Imagine my surprise when I couldn't find the clumps. I couldn't even find the hills! The Highway had been improved and the very curvature of the earth removed. These deciduous friends didn't have a chance. An attraction of this species is the size of the clump itself; seed can be collected from forms under twelve inches, a trait most useful in rock gardens or in hybridizing with its more strapping southern cousins. This iris is often found in clear cuts, or where trees have been removed. Flower size is equal to other species, and the color in Washington is primarily tones of blue and lavender-violet. White, cream, and yellow forms are reported, but are rare. In Oregon (I. Gormanii Piper) is a pale yellow form, and in Eastern Oregon and WA. we have the buff yellow subspecies I. klamathensis, well-veined brown or maroon. The Siskiyou subspecies I. Thompsonii is a beautiful purple, and where these mountain species overlap, color combinations dance to the full spectrum of their potential.

A lesser-known species is Iris macrosiphon, named for the long (macro) tube (siphon) of its flowers. It blooms in April or May in the grassy foothills of the Sacramento Valley. The 12-16 inch foliage is neat and fountain like. In the Bay Area, I fernaldii is somewhat taller and has arching blue-green leaves and graceful narrow-petaled cream-yellow blossoms. The violet I. mac. "Mt. Madonna" is a Suncrest Nurseries introduction, and if kept dry in summer may survive in western WA Iris chrysophylla is not (golden leafed), but the leaves are lighter green, and the plant is slender and diminutive. Some plants have nearly stem less, cream-white flowers, large and spidery, sometimes over 3 inches across. In its habitat, the bloom is in May or June. This Iris can be found in California and Oregon mountain or coastal forests. Genes for the shade! Iris munzii is much stouter and taller, often over two feet high, and has foliage tinged gray-blue to the green. The flowers are lavender to blue-violet and can be seen blooming in the foothills of the central Sierra Nevada.
Pacific Coast Hybrids are the garden party after this diverse group is planted together. A tumble garden of genes finds I. douglasiana easily crossing with I. innominata and I. tenax. Some breeders have recently included the genes of I. munzii and I. macrosiphon. All form handsome plants with an exceptional range of orchid-like color hues that like rainbows to May encourage and lighten. Hardiness for these hybrids should be to USDA zone 8. Northwest breeders are beginning to select even hardier strains. Both Aitkens Salmon Creek Gardens and Duane Meek in Oregon are developing new northwest introductions. So is Jean G. Witt of Seattle, who has crossed them with Siberian Irises. These "Cal-Sibe's" are even being tested in England. Losses of "P.C." Irises in winter are often due to improper drainage or divisions made too late in fall. Moving or division depends upon the species, but most are dig able even while blooming. Divisions are most successful in the cusp of Sept. and Oct. In the Pacific Northwest, late Sept. seems to be preferable, and spring divisions, aside from the more deciduous I. tenax are not recommended. When dividing, wait until white root hairs are seen growing. Without active root growth, the divisions may not survive. Seedlings are prolific as the plants self-sow easily. Cull out the poorer flowered, or those of interior form. Leave the remainder undisturbed, and fall mulch for winter protection. Cultivation is easy; the plants thrive in partial shade or in full sun. Their water requirements lend them to the wild garden. Regular summer watering is neither needed nor recommended. They can be left undisturbed and undivided for years. Mulch young divisions, and never over-divide. Once established leave them alone. No pampering, no fussing- my kind of plant! Best of all, they're native. Try planting them on the outskirts of your rhododendron garden -- you will be surprised at the effectiveness of this combination in toning down these bigger blossoms. With the addition of Purple Smoke trees, the softer blues, pale yellows, or mixed whites soften and harmonize the strong pinks and crimson- reds of Rhododendrons. A happy and most leaf-moldy odd couple. In the non-thirsty garden, one can plant a blue-purple wildness of them, mixing the later blooming California Poppies, Crimson Clover, Blue Eye Nemophila, and Hair Grass to dilute the summer conflagration. This combination can provide color from May until September. A spring planting of vibrancy, massing colors that reach from the sky to exhilarate-- a down splash of colors to dilute the green. Opposites attract! Antaeus, son and protector of Gaea (mother earth) finds himself touched by Iris, goddess of the rainbow, and where her feet have touched his skin, there bloom her namesakes. In a Northwest so blessed in rainbows, look for native Irises that mark her gentle rainbow passing.


Herb Senft