To garden successfully in Colorado without allowing the water bill to run amok has required that we accept our climate and its limitations and rethink our plant palette. In response, gardeners have embraced the concept of water-smart gardening or Xeriscaping.
Yet, one microclimate in our landscapes, dry shade, is a challenge for even the most ardent Xeriscaper.
Shade is a welcome commodity on a hot summer afternoon in the garden. It reduces evaporation, protects tender foliage from scorching and provides the opportunity to grow plants that will not live under the full intensity of the unfiltered Colorado sun. Shade from the winter sun often means that snow stays in place longer, insulating plants from the disruptive freeze-thaw cycle.
That said, the very trees that produce the shade also suck up most of the available soil moisture and fill the soil with competing roots, compounding the challenge of growing ornamental plants in the unique microclimate around the base of the tree.
As in other dry conditions, we can apply the standard principals of Xeriscaping, including amending the soil with organic matter to improve the water-holding capacity, selecting appropriate plants for the site and adding mulch to reduce evaporation. Providing additional water is key to helping just about any new plant become established, but once settled in, plants correctly chosen for dry shade can help keep the water bill in check.
When choosing plants for the dry shade microclimate, we can look for inspiration in other semi-arid regions around the world as well as to native plants found in the foothills a few miles away.
Ann Montague, Broomfield, is a Master Gardener with Colorado State University Cooperative Extension Master Gardener. For information on a variety of horticulture topics visit www.planttalk.org, or call the Colorado State University Cooperative Extension office in your county.
Plant ideas
Here are a few plant ideas for your dry shady site.
Groundcovers
English Ivy ( Hedra helix)
Periwinkle (Vinca minor)
Sweet Woodruff (Galium odoratum)
Deadnettle (Lamium maculatum )
Shrubs
Creeping Grape Holly (Mahonia repens)
Kinnikinnick (Arctostaphylos x coloradoensis)
Alpine Current (Ribes alpinum)
Perennials
Lady’s Mantle (Alchemilla mollis)
Pigsqueak (Bergenia cordifolia)
Coralbells (Heuchera sanguinea)
Hardy Geranium (Geranium pheum)
Hermann’s Pride (Lamiastrum galeobdolon)
Columbine (Aquilegia chrysantha)
Stinking Hellebore (Helleborus foetidus)
