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Prepare Your Garden for Winter Q&A

Winter Landscape Prep Q&A

Question: Do you have any special tips to prevent winter damage to landscape plants?

My first suggestion would be to pick winter-hardy plants. Most of us are in USDA hardiness zone 5 (average minimum winter temperatures between minus 10 and minus 20 degrees Fahrenheit). Warmer microclimates exist in the city and along the lake, while colder areas can be found in some parts of the countryside.

Even hardy plants may need some help when they are newly planted or young. They need protection from deer, rabbits, mice, winter wind and sun, salt spray, or piles of snow sliding off the roof or dumped by a snowplow. Try hardware cloth or spiral plastic tree protectors to protect tree trunks; 5' high circles of heavy wire to prevent deer browsing of branches and buds; plywood 'tents' to prevent roof slides from breaking branches; stakes and burlap to keep winter wind and sun (or salt spray) from browning evergreen foliage. Anti-desiccant sprays are available that will cut down on moisture loss from the foliage after the ground is frozen.

Do not fertilize after Aug. 1. Pruning after Aug. 1 should be limited to dead/diseased or crossing branches. Late fertilizing or pruning may stimulate late growth, which will be more susceptible to winterkill. Our heavy rains may have the same effect, but that cannot be helped. If we have a dry spell this fall, new and young plants should receive 10-15 gallons of water, each week, until the ground freezes.

Many perennials need a winter mulch of woodchips or bark to help prevent frost heaving during winter thaws. A bucket of unfrozen soil or mulch should be kept handy to cover exposed roots if frost heaving occurs anyway. Some plants overwinter better if the stems are not cut back until spring. These include hardy mums, lavender, sage, Russian sage, and butterfly bush.

It's best to keep the lawn mowed until winter to prevent disease.

Last but not least, try to avoid using salt as much as possible. Perhaps sand or dry kitty litter will provide enough traction, and avoid salt damage to the landscape.