Rock Spiraea

Rock Spiraea, Holodiscus dumosus, is a thicket-forming shrub in the rose family, Rosaceae. It is a medium-textured plant with green foliage and white flowers, growing at a moderate rate and able to reach roughly 4.5 meters under favorable conditions. Its spreading habit lets it build dense stands over time. The species is native to western North America, ranging from British Columbia, Washington, Oregon, California, Nevada, Idaho, Montana, Wyoming, Utah, Colorado, Arizona, New Mexico, and Texas, and extending south into several regions of Mexico. Across this territory it occupies varied sites, tolerating dry to moist ground and soils that are sandy, medium, or heavy clay, typically at a neutral to slightly alkaline pH of about 7 to 8. It prefers full sun but accepts partial shade and is hardy in zones 4 through 8. It has also been introduced to Great Britain. Its small fruits are edible and have been used to make tea, giving the plant value beyond ornament. The white blooms and green leaves suit native and ornamental plantings, though the shrub is not notably drought resistant and does best where some moisture is present. No medicinal uses are recorded in the available data, and fruits should be identified with confidence before any use.