Watering Trees And Plants In The Winter

Should You Water Trees and Plants in the Winter? Yes! They’re dormant, not dead. While it’s most critical for newly planted shrubs, trees, and perennials, watering all your vegetation during breaks in the frigid temperatures is important for healthy plants this spring. Dormant plants are at rest, conserving energy and living on stored nutrients, but they still need water access.

Watering trees and shrubs is important to underground pipes in the area. During the winter, soil shifting and freezing can cause cracks in water, sewer, and septic pipes. Tree roots are already “aware” there’s water in those pipes and, if they’re thirsty, the roots will push their way through any minor cracks to get at it. While plants aren’t as likely to do this—they don’t have the broad reach of tree roots, which tend to be equal in size to the tree’s circumference—they can invade cracks in your foundation. Damaged pipes and foundations are expensive, extensive replacements. Better to water the trees. While the weather doesn’t always make it possible, from about November till April, depending upon your geographic location, water at least once a month. If you have had a soaking rainfall or fully melted snowfall, you may be off the hook for that month. If you’re not sure, however, you can use a commercial soil-moisture content sensor to check. You can also do it the old-fashioned way: Dig a small hole down about six inches and feel the soil.

The trick with winter watering, as you may suspect, is to choose a day when the ground is thawed, the snow is gone, and the temperature is around 40° F. Apply the water between noon and 2 p.m., so the ground can absorb it before temperatures dip at night.

Soak the soil to a depth of about six inches for plants and deeper for trees (and don’t forget the expanse of the roots on a tree—don’t just water around the trunk!). For trees and shrubs, use these guidelines from the Colorado State University Extension:

Trees: Apply 10 gallons of water for each inch diameter of the tree. So, a two-inch diameter tree (measured about six inches off the ground) needs 20 gallons of water. Remember: Diameter is the measurement through the center, not the outside of the tree trunk, the circumference. You may need to approximate if you’re not into math, but that two-inch diameter tree we just mentioned measures about 6¼ inches around the trunk.

Shrubs: Newly planted shrubs, which are hopefully mulched, need about five gallons of water twice a month. If they’re established, once a month usually will do it. Shrubs that are over six feet tall need 18 gallons a month.

Recommendations for perennials vary. Newly planted plants need more water than established plants. The soil should be wet down to about six inches. The simplest way to do all this watering, of course, is an outside faucet and hose. Be sure to disconnect the hose when you’re finished. If you don’t, you’re risking pipe damage. With the hose connected, water won’t drain properly from the faucet and, when it freezes, the water will expand and could break the pipe.

Oh, yes, and did I mention the lawn? It’s probably thirsty, too.