Landscape Logic column: When the mountains fare better than the Front Range
When it comes to winter plant damage, the high country often sidesteps the losses that are more prevalent at lower elevations and along the Front Range, in particular. The very challenges that make gardening at altitude more difficult actually help mitigate plant loss in mountain areas.
Gardeners at altitude know they won’t be very successful pushing the limits on plant hardiness zones, whereas gardeners along the Front Range are tempted to try. The elevation and harsher climate that have narrowed the viable plant palette often make high country gardeners less prone to experiment. Over time, they have found the tried-and-true plants that are most likely to survive over the winter. They’ve got their story, and wisely, they’re sticking to it.
DAMAGE STARTING TO SHOW
For lower elevations and along the Front Range, this year’s spring thaw and greening is likely to reveal plant damage caused from a sudden November freeze that happened before many plants had a chance to harden. Depending on the plant, its exposure, microclimate and other factors, there may be no damage, minimal damage or significant damage. Soon, we will start to see the results.
Many deciduous trees that normally shed their leaves in the fall didn’t shed them due to the early freeze. This spring, those brown leaves will fall and become a spring clean-up chore. Twigs that died will need to be pruned.
Pine trees are already showing browned needles. Browned needles on pine trees may be somewhat hidden by new growth and damaged needles should drop off during the normal two to three-year cycle of needle drop. Some other evergreens, like boxwood, are also showing freeze damage and will require pruning to remove the dead material.
PRUNE DEAD BRANCHES
Flowering trees and shrubs may have lost spring flowers due to buds that were set last August being frozen. Consequently, crabapple and apple trees may flower and fruit less this year. Buds that were protected by snow may have been insulated sufficiently that they did not freeze and will bloom. At normal bloom time, the damage will be evident. Once you can see which twigs or branches are dead, schedule to have them pruned.
For roses, wait to see what parts of the plant have been damaged and cut them back to the new growth.
PLANTS THAT WILL NOT BE AFFECTED
Hardy shrubs such as viburnum and the common lilac, which even thrives in Leadville, will probably fare better than less hardy plants such as forsythia and flowering quince. Later-blooming plants such as potentilla and spirea that set their buds on new growth will also be less likely to have damage. Perennials — daisies, peonies, daylilies, etc., — are not expected to be impacted because they bloom on this year’s growth.
Wherever you live in Colorado, growing and sustaining healthy plant material is an ongoing challenge. Fortunately, we have a well-educated green industry plus the resources of the Colorado State University Extension and organizations such as Plant Select to guide us.
Properly selecting plants for their location, along with ongoing maintenance, create landscapes that are healthy, harbor fewer weeds and require less water and outside treatments.
Becky Garber is a member of the Associated Landscape Contractors of Colorado, of which Neils Lunceford, a landscaping company, is a member. You may contact them at 970-468-0340.