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Morning Sun
  • The Gardener Within: Protect perennials from the coming freeze

  • For gardeners in northern USDA hardiness regions (starting around Zone 5), summer always ends, and winter always arrives, a little too soon. These colder regions have some special needs for protecting certain plants that just wouldn't notice the cold if they were a little further south.

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  • For gardeners in northern USDA hardiness regions (starting around Zone 5), summer always ends, and winter always arrives, a little too soon. These colder regions have some special needs for protecting certain plants that just wouldn't notice the cold if they were a little further south.
    Torch lily tie-up: Many perennials just evade winter trauma by going dormant, and can be cut back to give the garden a neat, tidy look over winter. However, if the roots or crown of the African native torch lily (kniphofia spp.) sit in water or freeze solid, the torch is toast. In areas where an insulating blanket of snow comes early and stays late, the ground may not freeze at all and the plant will come through just fine.
    But don't take the chance. Sometime before frost has penetrated the soil, protect the center of the plant by bundling the foliage up and tying it in place over the crown like a ponytail. Spread a thick layer of mulch about 18 inches around the crown, leaving 2-3 inches uncovered to discourage rot.
    Other perennials, like lungwort (Pulmonaria spp.), coral bells (Heuchera spp.), hardy mums (Chrysanthemum spp. and not to be confused with "florist" mums that are common around Halloween time) and ornamental grasses don't need to be trussed up, but do endure winter better with their foliage intact. Wait until late winter or early spring to cut them back, and do so before new growth gets too far along.
    Protect your trunks: Winter weather is unpredictable at best. Nighttime temperatures can plunge to subzero after a warm, sunny day. This will cause frost cracking, expansion and contraction of different areas of the bark of susceptible trees, especially those younger than 5 years old. There's no way to prevent all frost cracks, but there is something you can do to reduce the chances of that happening.
    Many fruit trees are especially susceptible to cracking. Orchard owners have been painting fruit tree trunks for years with white latex paint to reflect light and heat from the trunk and keep bark temperature more consistent. But it's not the most aesthetic solution in a home garden. Alternatively, wrapping the trunks with paper or plastic guards in late fall can accomplish the same goal without the unsightliness. These wraps, available online or at nurseries and garden centers.
    Wrap around the trunk bottom to top, like shingles on a roof, from ground level to just below the first branches. This way water is more likely to run off rather than be channeled between the wrap and the bark. Remove the wrap in April so it won't shelter insects. Trees most prone to frost cracking include cherry (Prunus spp.), maple (Acer spp.), apple (Malus spp.), ash (Fraxinus spp.), beech (Fagus spp.) and sycamore (Platanus occidentalis).
    Page 2 of 2 - Cover the roses right: Those Styrofoam cones used to protect roses can save some work, but they must be used correctly. Don't just plop them over the bush and walk away; they can bake the rose to death come the first warm, sunny winter's day. Instead, punch several holes about an inch in diameter around the top of the cone to let warm air escape. Cut back the canes just enough to slip a cone over the bush, and, once the first hard freeze has occurred, stuff with dry leaves or straw. Weight the cones down with a brick or other heavy, stable object to secure them against heavy winter winds.
    Micromanage the climate: With a little extra care and planning, you can grow the almost hardy perennials and trees you love by tweaking your garden's microclimates. For example, crape myrtle (Lagerstroemia indica) is cold hardy in Zones 7-9, but does all right in temperatures above the mid-20s. Grow them in containers and move them into an unheated garage or basement in the winter. Water occasionally until it's time to move them back outside.
    Joe Lamp'l, host of "Growing a Greener World" on PBS, is a Master Gardener and author. For more information visit www.joegardener.com.

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