The plants in our gardens are undergoing a lot of change, transferring energy to their root systems, preparing for winter and getting ready for spring growth. We can take a lesson from our plants, by getting our gardens ready for the onset of winter. By plan-ning now, we can help plants get off to a good start this spring. The following sugges-tions may help you develop your own winter preparation “checklist”:

Lawns
• Mow at a two to three inch height. No scientific evidence justifies mowing your lawn shorter in late fall. Research shows that mowing to less than two inches can result in decreased drought tolerance and higher incidence of insects, diseases and weeds.
• During extended winter dry periods, it is good practice to water the lawn once per month, if the ground is thawed and will absorb water. Pay particular attention to exposed slopes, sites with shallow soil, and south- or west-facing exposures. Ex-cessively dry areas may be prone to spider mite infestation.
• “Winterize” your lawn by applying at least one pound of nitrogen per 1,000 square feet. A natural organic fertilizer, like dehydrated poultry waste can be ap-plied at twice the rate.
• Aerating helps improve the root zone by relieving soil compaction while control-ling thatch accumulation. Aeration can also be done in April.

Trees
• If you compost yard waste, consider saving some raked leaves to add to your compost pile in the spring. Whole leaves are better than leaves that have been shredded or mulched with a lawn mower, because finely chopped leaves may re-strict air circulation needed for effective decomposition.
• Dispose of diseased leaves, especially if you had insect or disease problems this summer. Left on the ground, they can harbor fungal diseases over the winter and reinfect your plants in the spring.
• If possible, water trees once per month, but only when air temperatures are above 40 degrees. Water at mid-day to allow adequate saturation before freezing at night.

Perennials
• Perennials that provide winter interest or seed for the birds should be left stand-ing until early spring, which also protects the crowns from winter kill. Coneflower, butterfly bush, sage, hyssop and yarrow are examples of plants that can be left alone until spring. Ornamental grasses add texture as well as food and cover for birds in the fall and winter. Plan to cut these plants back in early spring, before new growth emerges.

Mulch
• With roses, it is important to protect the crowns, where the main canes emerge, before the first hard freeze occurs. A mixture of soil and leaves or pine needles covering the first six to eight inches above ground works well.
• After the soil has frozen, mulch other flower beds and specimen plants. Shredded wood products or leaf compost makes good mulch. Be sure to keep mulch six inches away from the trunks of trees and shrubs, to avoid creating a cozy winter ”nest” for insects.

Watering
• In dry winters, all shrubs benefit from supplemental watering, but trees and shrubs planted this summer are still adapting and need more water than plants that have been in the soil for at least one year.
• Five gallons of water applied two times per month is a good rule of thumb for a newly planted shrub. Established shrubs, less than three feet tall, will do fine with five gallons per month. Established shrubs, taller than six feet, need 18 gallons per month. Be sure to apply water within the plant's drip line and around the base.
• For more information on watering during the winter, see CSU Extension Fact Sheet #7.211 “Fall and Winter Watering”

Tools and Planters
• When your winter preparation is done, take time to clean, oil and sharpen your gardening tools. Wash them with soap and water, using a wire brush to remove stubborn soil deposits. Steel wool is useful to remove rust.
• Sharpen pruners and shovel blades. This is also a good time to remove and sharpen mower blades.
• Before storing your tools, wipe with a lubricating oil to prevent rust.
• Remember to empty ceramic pots to prevent cracking caused by freeze and thaw cycles.

The authors have received training through Colorado State University Cooperative Extension's Master Gardener program and is a Master Gardener volunteer for Larimer County.

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This page updated:  October 19, 2007