High Altitude Gardening

Many varieties of perennials do well in mountain settings. Mountain gardeners should select perennial varieties that bloom early to mid-summer such as brown-eyed Susans, sunflowers, painted daisies, and yarrow.

Our state flower, the columbine, grows wonderfully and reseeds plentifully. Gaillardia is a native blanket flower. Sulphur flower, a native plant, will work well scattered throughout the yard as will blue flax, an excellent erosion-control plant.

Delphinium is one of the best for mountain gardens. The pansy is a biennial but may act as an annual or perennial, depending on growing conditions. Bearded iris and Siberian iris make showy beds of blooms. Tiger lilies, oriental poppies, sweet peas, hollyhock, and sweet William top the list for showy, mountain blooms.

After the Beetle, Replant and Reforest
Consider mitigating the risks associated with wildfire when revegetating around your home after beetle-kill trees have been removed. Plant aspen trees, nature’s firebreak. It takes a lot of heat energy to burn green aspen. The Colorado State Forest Service recommends these hardy trees for 9,500ft or above: green ash, Rocky Mountain maple, aspen, Colorado blue spruce, Engelmann spruce, and bristlecone pine. It is also safe to plant lodgepole pine. Although the pine beetle has decimated these trees, they are native to our state and should be replanted in our forests.

Do not Landscape with Flammable Plants
These are plants with leaves high in oils or resins such as junipers. If you’re unsure, consult with a landscape architect, horticulturist, or forester with knowledge of and experience in fire safety.

Warning against Noxious Weeds
While noxious weeds are often pretty, their effects are not. With no natural enemies in their new environment, the weeds are able to spread uncontrollably. As the noxious weeds multiply, the number of native plants can be vastly reduced. Noxious plant species of particular concern to locals include: scentless chamomile; yellow toadflax, which is common in soil disturbed by utility construction or fire; Canada and musk thistle, a biennial weed that can grow up to eight feet tall; and the oxeye daisy, a showy, pretty plant that crowds out native grasses. Commonly confused with the Shasta daisy, the oxeye can be identified by a dimple in the center of the yellow portion of the flower and a faint “wet dog” smell.

Control requires removal of the plant and entire root system. The key to keeping them from returning is keeping a healthy, native-plant community that will shade out the invaders. Never let these weeds go to seed. Keep an eye out for seed heads and pull the weed, or at least cut off the seeds.

High-Altitude Zones
You will see mention of “zones” in relation to gardening. Climate zone maps were created to help gardeners know where a plant is known to grow well. If you want a shrub, perennial, or tree to survive and grow, the plant must tolerate year-round conditions, such as the lowest and highest temperatures and the amount and distribution of rainfall. The Denver Metro area and the surrounding plains are considered zone 5. Moving above Golden, the zone changes to zone 4. As you reach the mountains, the zone drops to 3. As a general rule you can grow any plant with a zone number equal to or lower than your zone.

For trees, plants, and cut flowers go to Margaret’s Garden in Tabernash, (970) 726-1273,
www.margaretsgardenonline.com.