[The Genus Lewisia East of the Cascade Mountains of Oregon and Washington]
Wallowa Lewisia is an attractive wildflower which may be used in the rock garden. It is a succulent perennial with a thick, well branched, fleshy root with numerous basal leaves in a basal rosette. The basal leaves are linear-oblanceolate to narrowly spatulate, with tips ranching from acute to rounded, and they range from 2-10 cm long and 3-8 mm wide. There are usually several to many flower stems, these ranging from 10-30 cm high, and several entire to serrate bracts may be found on the stem.
The inflorescence is a many-flowered panicle. Individual flowers have 2 glandular-dentate sepals from 1.5-2 mm long and 7-9 white with pink venation to magenta-rose petals from 5-13 mm long. There are 5-6 stamens.As mentioned above, Columbia Lewisia is an attractive plant (especially variety rupicola) for the rock garden. It is best suited for drier, east side (of the Cascades) gardens, but can survive for several years in west side gardens if given sufficient ventilation or provided with cover to protect it from the rain. I either put it in a rock garden covered by plastic sheet, or protect individual plants with clear, plastic bird feeder covers. Individuals left in the open have survived winter wetness, but they need to be well clear of other plants and need to be away from areas where water can collect. Columbia Lewisia produces baby plants by offsets from the crown of the rootstock. These may be carefully broken off in the fall or late winter and planted in gravelly or sandy soil to produce new plants.
Three varieties of Columbia Lewisia may be found. These include:
1. Lewisia columbiana var. wallowensis - Basal leaves obtuse to acute-tipped, mostly less than 4 cm long, fewer in number, and thinner. The lower bracts on the stems are entire margined, while the upper ones are serrate. The bracts are not glandular. The plants range from 5-15 cm tall. The petals range from 5-8 mm long and are white with pink stripes to pink overall. Found in the Wallowa Mts. and rim of the Snake River canyon of northeastern Oregon, and in the Seven Devils Mts. of adjacent Idaho.
2. Lewisia columbiana var. columbiana - Basal leaves numerous, obtuse to acute-tipped, from 3-10 cm long and up to 8 mm wide. The stems have bracts with entire margins to at least mid-length. The bracts are never glandular. The plants range from 15-30 cm tall. The petals range from 7-10 mm long and are white with pink stripes to pink overall. Found in the Columbia River Gorge north on the east side of the Cascades to Okanogan County, WA and probably into adjacent southern British Columbia.
3. Lewisia columbiana var. rupicola - The basal leaves are rounded. The lowest bracts on the stems are serrate margined and generally glandular. The flowers are light to deep pink or rose. Found west of the Cascades in the Olympics south to Saddle Mt in Clatsop County, OR, and at Mt. Rainier.
Wallowa Lewisia may be found on exposed gravel bands, rocky slopes and rocky ledges.
Wallowa Lewisia may be found on both sides of the Cascades from southern British Columbia south through the Olympic Mts. and coast ranges to northwestern California, and further south in the Sierra Nevada. It may also be found in central Washington, northeastern Oregon (Wallowa Mts.) and adjacent Idaho (Seven Devils Mts.).