Rock Columbine in the Landscape
Stephen Love, University of Idaho
Scientfic Name: Aquilegia scopulorumCommon Name: Rock Columbine, Utah Columbine
Description: Rock columbine is a dwarf, herbaceous, very long-lived perennial. The plants die back to the ground during winter. New shoots emerge early in the spring and develop into a dense clump of very attractive, divided, blue leaves. The upward-facing flowers grow on short stems, creating the impression the blooms are floating just above the foliage. The flowers are long-spurred and light to dark blue in color. Bloom period is fairly long, May to July, often with full rebloom later in the summer. Rock columbine can withstand moderate drought conditions and is a good subject for dry shade or beds and borders in full sun. This species makes an exceptional rock garden specimen.
Native Habitat: Aquilegia scopulorum is native to mountain ranges in western Utah and eastern Nevada. Plants grow in subalpine communities on limestone or igneous slopes. Found at elevations ranging from 7,000 to 11,000 feet.
Cultural Requirement
Soil: Tolerates a wide range of soils, including clay, and/or those with high pH.
Moisture Tolerance: Thrives under a wide range of conditions, from moderately moist to dry. Will not look as nice or flower for as long under extended xeric conditions.
Sun/Shade/Preference: Grows well and blooms adequately in full sun or in light to moderate shade.
Transplanting: Easily transplanted, both from pot to pot and from pot to garden. Can withstand long-term culture in pots up to one gallon size.
Propagation: Best grown from seed. Cold stratification (optimal timing undetermined, but 8 weeks seems adequate) is required for maximum germination. Even after stratification, germination can be sporadic and is sometimes low. Once emerged, seedlings are easy to handle and transplant nicely when they have 4 to 6 true leaves. Smaller seedlings have a lower survival rate during handling. Plants can also be propagated by rooting basal stem cuttings.
Maintenance (pruning, fertilization, deadheading, division, irrigation, etc): Rock columbine requires minimal maintenance. Remove spent flower stems to improve appearance and encourage secondary bloom. Apply supplemental irrigation if the leaves begin to show signs of stress. A small amount of nitrogen fertilizer can help invigorate older plants.
Insect, disease, or other problems: Rock columbine is commonly infested by aphids, spider mites, and powdery mildew, problems that are common to most columbine species. Aphids seldom reach populations that require control measures, but when they do, control options include insecticidal soap or an appropriate insecticide. Spider mites and powdery mildew affect the plants in late summer as the leaves age. If these pests make the plants unattractive, it is best to remove the old foliage to encourage production of new, attractive foliage.
Landscape Value
Use in the Landscape: Rock columbine is one of the most interesting and beautiful species in the genus. It makes an outstanding specimen plant in a rock garden. It can also be used to bring interest to shady areas or to accent other plants in beds, borders, or vertical gardens. Rock columbine is effective in a trough or pot. This plant is amenable to either formal or naturalized designs and can be incorporated almost anywhere in the landscape where a small plant is required.
Weediness/Invasive Potential: Rock columbine is a clump-forming plant and does not spread via rhizomes or stolons. It will occasionally produce volunteer seedlings immediately around the parent plant. These are easily controlled and do not represent invasive behavior.
Foliage: Foliage of rock columbine is blue in color and forms a tight mound. The leaves are compound (twice divided) into three leaflets, thus creating a lacy appearance.
Flower: The flowers are light to medium blue in color and are large in relation to the dimensions of the plant. Short flowering stems hold the blooms just above the foliage. Flowers are long-spurred, up to 3 inches long, and upward-facing.
Timing: May-August
Fruit: The fruit is a terminal capsule-like structure called a follicle. It is divided into five papery segments, each holding numerous oval, shiny, black seeds.
Form: The form is a dense mound.
Texture: Fine.
Ultimate Size: Prior to bloom, the plants are 4 to 6 inches tall and 8 to 10 inches wide. In flower the plants are 7 to 10 inches tall.
Rate of Growth: Plants of rock columbine are relatively slow growing and usually require 3 to 4 years to reach mature size. In spite of the slow growth, they often bloom the first year after transplanting to the garden.
Suggested Plant Partners: Place rock columbine in front of taller plants, like Erigeron speciosus, Delphinium occidentalis, and Helenium hoopesii, or around trees and shrubs such as Acer glabrum, Quercus gambelii, Ericameria nauseosa, and Dasiphora fruticosa. Also, use in a rock garden amongst other diminutive plants such as Antennaria rosea, Campanula parryi, Eriogonum ovalifolium, Geum triflorum, and Heuchera cylindrica.
Availability: Difficult to find as potted plants. Seed can occasionally be purchased from native plant societies and native plant seed suppliers or garden societies.
Cultivars: None.
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