Colorado's high elevation and temperate climate creates a unique and challenging environment for plant growth. When selecting plants for a rock garden in Colorado Springs, consider the size of the rock garden, the steepness of the incline, and the amount of foot traffic through the garden area. Additionally, rock garden flora in Colorado should be resilient and hardy, categorized by the United States Department of Agriculture (USDA) with a hardiness zone rating of 2 to 4. Plants in this zone are able to survive cold, snowy winters and the low oxygen environment found 7,500 feet above sea level.
Prickly thrift (Acantholimon) is a perennial, evergreen plant with sharp, prickly leaves with white and pink flowers blooming early to mid-summer. Prickly thrift can grow to 8 inches in height with a wide spread of nearly 18 inches. Preferring full sunlight, well-drained soil and requiring low amounts of moisture, prickly thrift is a popular rock garden plant that is deer- and rabbit-resistant.
Woolly yarrow (Achillea tomentosa) is a mat-forming, low-level shrub with grey-green leaves and yellow flowers blooming mid-summer. With a height of 6 to 12 inches, this easy-to-grow rock garden plant prefers direct sunlight and well-drained soil. Woolly yarrow is used within rock gardens as a walkway and floral border.
Lady's mantle (Alchemilla) is a Colorado rock garden plant with a mounding base, large, rounded, lobbed leaves and yellow-green flowers blooming early to mid-summer. Preferring direct or partial sunlight and well-drained, moderately organic top soil, lady's mantle is easy to grow and wildlife-resistant.
Alyssum (Alyssum spp.) is a low-growing rock garden plant with hairy grey leaves and fragrant yellow flowers blooming in early summer. With a maximum height of 3 inches, Alyssum is a mat-forming plant that grows in thick, dense clusters that require full sunlight and well-drained, moist soil.
Lily of the Valley
Lily of the valley (Convallaria majalis) is a distinctive rock garden plant with large, glossy, green leaves and delicate, fragrant, drooping, white-pink flowers hanging from the top of the central stem in large clumps. Lily of the valley blooms in early spring, has a height of 6 to 9 inches and prefers shady, damp environments and organic soil.