Watering of trees, shrubs, lawns, and perennials during prolonged dry fall and winter periods prevents root damage that affects the health of the entire plant. Colorado’s’ dry air, low precipitation, little soil moisture, and fluctuating temperatures and just the characteristics of fall and winter can be hard on trees and shrubs and requires winter tree watering. There often can be little or no snow cover to provide soil moisture, particularly from October through March.
Trees, shrubs, perennials and lawns can be damaged if they do not receive supplemental water. The result of long, dry periods during fall and winter is injury or death to parts of plant root systems. Affected plants may appear perfectly normal and resume growth in the spring using stored food energy. Plants may be weakened and all or parts may die in late spring or summer when temperatures rise. Weakened plants also may be subject to insect and disease problems.
Woody plants with shallow root systems require supplemental watering during extended dry fall and winter periods. These include but are not limited to: European white and paper birches; Norway, silver, red, Rocky Mountain, and hybrid maples; lindens, alder, hornbeams, dogwood, willows, and mountain ash. Evergreen plants that benefit include spruce, fir, arborvitae, yew, Oregon grape-holly, boxwood, and Manhattan euonymus. Woody plants benefit from mulch to conserve soil moisture. Established large trees have a root spread equal to or greater than the height of the tree. Watering should be done directly to the most critical part of the root zone.
Newly established lawns, whether seed or sod, are especially susceptible to damage. Susceptibility increases for lawns with south or west exposures. Contact American Tree today for a free estimate and landscape evaluation.
Tree & Shrub Watering Basics
- Winter watering should be done from October through March.
- Water only when air temperatures are above 40 degrees F.
- Apply water at mid-day so it will have time to soak in before possible freezing at night.
- Monitor weather conditions and water during extended dry periods without snow cover—one to three times per month.
- Trees obtain water best when it is allowed to soak into the soil slowly to a depth of 12 inches.
- Methods of watering trees include: sprinklers, deep-root fork or needle, soaker hose or soft spray wand.
- Apply water to many locations under the dripline and beyond if possible.
- If you use a deep-root fork or needle, insert no deeper than 8 inches into the soil.
- As a general survival rule, apply 10-20 gallons of water for each diameter inch of the tree.
- Newly planted shrubs require more water than established shrubs that have been planted for at least one year.
- Apply 5 gallons two times per month for a newly planted shrub.
- Small established shrubs (less than 3 feet tall) should receive 5 gallons monthly.
- Large established shrubs (more than 6 feet) require 18 gallons on a monthly basis.
- Decrease amounts to account for precipitation.
Read more published information from Colorado State University at the link below.