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How do I protect my perennials for winter?
Garden perennials which are cold hardy can still be damaged when the soil freezes and thaws several times during the winter. This freezing and thawing of the soil may loosen or heave the plants, causing roots to break and dry.
A 2" to 4" layer of organic mulch, such as leaves, compost, wood chips or shredded bark will give winter protection to perennials by preventing these rapid temperature changes of the soil. This mulch will also reduce deep penetration of frost and excessive loss of moisture. The mulch should be applied after the soil begins to freeze.
A final word of caution: For added protection, be sure to buy perennials that are winter hardy in this area. A reliable nursery or garden supply center will be able to guide you in your selection. Also, avoid planting perennials in poorly drained locations where they might be subject to winter root rot.