Centennial Winter Watering: The Yard Chore That Does Not End With the Sprinklers

At some point every fall in Centennial, the sprinkler system gets blown out, the hoses are disconnected, and we mentally close the book on watering until spring.

Colorado has other plans.

Our Front Range winters are often dry, sunny and windy, with long stretches when there is little or no snow covering the ground. That combination can quietly pull moisture from the soil even while plants appear dormant.

According to Colorado State University Extension, trees, shrubs, lawns and perennials can suffer root damage during prolonged dry periods in fall and winter. The effects may not even become obvious until late spring or summer.

So yes, Centennial, you may need to water the yard in January.

The 40-Degree Rule

Fortunately, winter watering does not mean standing outside with a garden hose during a snowstorm.

The basic rule is wonderfully simple:

Water when the temperature is above 40 degrees, the ground is not frozen, and there is no meaningful snow cover providing moisture.

CSU recommends watering during the warmer part of the day so the water has time to soak into the soil before nighttime temperatures fall. During extended dry periods, that may mean watering once or twice a month.

Think of it as checking in on the landscape rather than restarting your summer irrigation schedule.

Newly Planted Trees Need Extra Attention

Remember that beautiful new tree you planted this year?

It is not fully established just because the leaves have fallen.

Newly planted trees are especially vulnerable to winter drought. CSU notes that a tree can take roughly a year to establish for every inch of trunk diameter. A two-inch tree, for example, may need at least two years before its root system is well established.

A useful guideline from CSU is approximately 10 gallons of water per inch of trunk diameter for a newly planted tree during a watering session.

The important part is where the water goes.

Do not simply pour it against the trunk. Let water soak slowly into the soil throughout the root zone beneath and around the tree's canopy.

Roots are doing the drinking. The trunk is merely standing there looking important.

Evergreens Are Thirstier Than They Look

Colorado evergreens deserve special attention.

Pines, spruces, junipers and other evergreens continue losing moisture through their needles during winter. Dry winds and warm winter sunshine can accelerate that moisture loss.

CSU specifically notes that most evergreens growing in Colorado landscapes benefit from supplemental watering during winter dry spells.

If you have an evergreen on the south or west side of the house, keep an especially close eye on it.

Those areas receive more reflected winter heat and often dry faster.

The same is true for landscaping exposed to our enthusiastic Colorado wind.

Don't Forget Shrubs and Perennials

Trees tend to get all the attention because they are large, expensive and difficult to replace.

But shrubs and perennial beds can suffer from winter drought too.

Freeze-and-thaw cycles can create cracks in exposed soil, leaving roots vulnerable to drying and cold temperatures. Mulch helps conserve moisture and insulate roots, but it does not replace water when the soil becomes genuinely dry.

Late-planted perennials, new shrubs and plants in exposed southwest-facing beds are particularly worth watching.

If you added plants during that wonderful fall planting window we talked about earlier in this series, winter watering is part of finishing the job.

Snow Does Not Always Mean "Watered"

Here is another Colorado wrinkle.
A snowy yard does not necessarily mean the landscape received much usable moisture.

Light, fluffy snow can contain surprisingly little water, while heavier snow may provide considerably more.

CSU recommends watering woody plants monthly when natural precipitation between October and April is less than about one inch.

Instead of judging by how picturesque the backyard looked after Tuesday's snowstorm, check the soil.

If the ground is unfrozen and dry several inches down, your plants may appreciate a drink.

Water Slowly, Not Dramatically

Winter watering should be boring.

That is a compliment.

A slow trickle from a hose, sprinkler or soft spray wand gives water time to penetrate the soil instead of running across frozen or compacted ground.

For mature trees, remember that roots extend well beyond the trunk. CSU notes that the root spread of an established large tree can be equal to or greater than the tree's height.

That means watering a tiny circle around the trunk of a 30-foot tree is a little like serving Thanksgiving dinner on a bottle cap.

Spread the water throughout the important root zone.

Nick's Can Help You Prepare

If you are not sure whether a tree needs additional water, how much mulch to use, or whether a particular shrub is vulnerable to Colorado winter conditions, Nick's Garden Center & Farm Market remains a useful local resource.

Nick's specializes in trees and shrubs suited to Colorado landscapes and emphasizes choosing plants based on light, available space and water requirements. Their garden professionals can also help homeowners think through care for newly planted trees and shrubs before winter settles in.

Nick's Garden Center & Farm Market
2001 S. Chambers Road, Aurora
303-696-6657
Visit Nick's Garden Center

Your Simple Centennial Winter-Watering Check

Once or twice a month this winter, take a look outside.

Has it been unusually dry?

Is there little or no snow on the ground?

Is the temperature above 40 degrees?

Is the soil unfrozen?

If the answer is yes, your trees, shrubs and perennial beds may need water.

Colorado gardening does not completely stop when winter arrives. It simply gets quieter.

And sometimes the difference between a tree that struggles next summer and one that bursts back to life is a garden hose on a sunny 45-degree January afternoon.