Winter watering for dry landscapes

    1

    Woody plants with shallow root systems require supplemental watering during extended dry fall and winter periods. These include 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.
    Herbaceous perennials and ground covers in exposed sites are more subject to winter freezing and thawing. This opens cracks in soil that expose roots to cold and drying. Winter watering combined with mulching can prevent damage.
    Lawns also are prone to winter damage. Newly established lawns, whether seed or sod, are especially susceptible to damage. Susceptibility increases for lawns with south or west exposures.
    Watering guidelines
    Water only when air temperatures are above 40 degrees Fahrenheit. Apply water at mid-day so it will have time to soak in before possible freezing at night. A solid layer (persisting for more than a month) of ice on lawns can cause suffocation or result in matting of the grass.
    Plants receiving reflected heat from buildings, walls and fences are more subject to damage. The low angle of winter sun makes this more likely in south or west exposures. Windy sites result in faster drying of sod and plants and require additional water. Lawns in warm exposures are prone to late winter mite damage. Water is the best treatment to prevent turf injury.
    Monitor weather conditions and water during extended dry periods without snow cover — one to two times per month.
    Newly planted versus established plants
    Newly planted trees are most susceptible to winter drought injury. Woody trees generally take one year to establish for each inch of trunk diameter. For example, a 2-inch diameter (caliper) tree takes a minimum of two years to establish under normal conditions.
    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 drip line 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 gallons of water for each diameter inch of the tree. For example, a 2-inch diameter tree needs 20 gallons per watering. Use a ruler to measure your tree’s diameter.
    Newly planted shrubs require more water than established shrubs that have been planted for at least one year. The following recommendations assume shrubs are mulched to retain moisture. In dry winters, all shrubs benefit from winter watering from October through March. 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. Water within the drip line of the shrub and around the base.
    Herbaceous perennial establishment periods vary. Bare root plants require longer to establish than container plants. Perennials transplanted late in the fall will not establish as quickly as plants planted in spring. Winter watering is advisable with late-planted perennials, bare root plants, and perennials located in windy or southwest exposures. For more information, contact the Colorado State University (CSU) Extension Office at -5931.
    Upcoming events
    January/February 2020: Support your local 4-H Program by purchasing soup from a 4-H member.
    Jan. 18, 2020: Cottage Foods Certification, 8:30 a.m. to 1 p.m. at the Extension office. This certification allows certain foods to be produced in home kitchens and be sold directly to the consumer. For more information, please call the office at 264-5931. To register, go to www.eventbrite.com/cottage-foods-pagosa-co-tickets-83416072719 or come into the office to pay. Cost is $40
    Feb. 11, 2020: The 36th annual Beef Symposium will be held at the Archuleta County Extension office. The cost is $25 per person and includes lunch. Please call the Extension office at 264-5931 for more information and to register.
    Feb. 12, 2020: The Agricultural Financial Management Strategies workshop hosted by the CSU Agriculture and Business Management Team will cover topics such as risk management, business planning, enterprise budgeting, record keeping and more. Please go to www.2020fms.eventbrite.com to register or come into the office to pay. The cost is $15.