US National Arboretum


Pest Management

Pest Management Tips: December

image of a ladybug    It is still a great time to plant many types of woody trees and shrubs. As the days shorten and soil temperatures cool, plant growth slows. This is an ideal time to plant as trees are more forgiving of transplant. You can successfully plant up until the ground freezes. It is best to plant when the soil is evenly moist; plan to plant 2 to 3 days after a significant rain event. Mulch newly planted saplings to protect from winter extremes. Remember to keep new plantings well watered up until freeze.

image of a ladybug    Instead of cutting back herbaceous perennials, try leaving them for the winter. They provide foraging and shelter sites for birds and other creatures. Ornamental grasses also add off season interest to a garden at a time when flowers are fading fast. Dried foliage and flowers of many perennials and herbaceous plants can be used in holiday arrangements, wreaths and other seasonal items.

image of a ladybug    It's not too early to start planning next years garden. Make a note of which plants fared poorly, and start thinking about suitable replacements. If you have areas in your garden with persistent problems, amend the soil with compost to improve structure and texture. Check for good drainage prior to planting by partially filling holes with water. If water does not drain in a half hour, you probably have a drainage problem. Correct the situation by digging deeper and widening the planting area. Try rotating to a different species if you have repeatedly failed with one species in a given location.

image of a ladybug    With the dormant period just around the corner, it is time to begin winter preparation in the garden. Annual flowers and vegetables that have begun fading should be removed. Removing dying crops will reduce the severity of pests and diseases over wintering in the garden, and encourage a healthy start next spring. As you pull out spent plants, incorporate ground leaves or other finely chopped organic matter into the soil to add depleted nutrients.

image of a ladybug    With winter just around the corner, it is time to think about de-icing options. Sand is a good product for driveways and sidewalks. Sand will not damage plants or turf when it is eventually washed off into turf or bedding areas. Rock salt is an effective de icer, but does not work well below about 20 degrees Fahrenheit. Salt is notoriously corrosive to metals and is toxic to many landscape plants, so be careful where you use it. Do not use salt products on driveways and sidewalks if you have desirable plants nearby. Rock salt is also damaging to vehicles if it gets on any painted or unpainted metal surface. Calcium chloride is another good alternative to rock salt.

image of a ladybug     Nuisance insects are sometimes a problem for homeowners as falling temperatures drive critters to seek out shelter or a protected place for the winter. If you are encountering significant numbers of migrating insects, simply vacuum them up and release them outside. Do not squish them; some contain colorings that may stain carpet or rugs. Others may release noxious odors. Most of the common insects that migrate indoors -- ladybugs, box elder bugs, squash bugs, crickets -- are harmless, so no need to worry. Some are beneficial insects, so why not just release them into the garden.

image of a ladybug     Snow accumulation on landscape plants can be a disastrous situation. Heavy, wet snows will splay and snap branches, leaving plants damaged and disfigured. There are several different directions you can take when dealing with this inevitable winter problem. The best thing to do is to carefully brush away snow as it falls, never allowing it to mount to damaging levels. During a heavy snowstorm, this may require 3 or 4 trips to the garden! If this is not practical, try to remove snow as soon as possible, but before it re freezes to an icy, solid state. Once it has frozen, it should be left alone, and allowed to melt at its own pace. You can actually cause more damage by trying to remove it at this stage. To remove snow from tall plants, use a broom and brush very carefully. Plants that are especially susceptible to winter snow and ice injury (boxwood, arborvitae) can either be tied up or covered to minimize or prevent injury.

image of a ladybug     Cold winter winds can cause injury to evergreens. Needles and leaves of evergreens may become discolored or develop a bleached out appearance, especially on windy sites. "Winter burn" is caused by the wind blowing over leaf surfaces and drawing water out of the plant, desiccating the plant tissue. Locations in full sun tend to fare worse. To protect plants, be sure soil is evenly moist up until freeze. During a dry fall, you may need to water up until the ground freezes. You may also want to consider protecting plants by wrapping them in burlap or putting up some sort of barrier to break the wind. Another option is the anti desiccant spray. These are available from your local nursery or garden center. Anti desiccant sprays create an invisible film on the leaf surface that reduces the amount of water lost to the wind and sun. If you choose to try an anti desiccant, be sure to read and follow the product labeling.

image of a ladybug     Secure your pesticide inventory for the off season. Proper storage is essential to ensure that chemicals retain their potency and consistency. It is best to store pesticides in a dry location that is relatively temperature consistent. A garage may be a suitable choice of sites, but be sure that there is no safety hazard to children or pets. Ideally, you should have a small cabinet for pesticides alone, and secure it with a padlock. If there is any chance of water invading the area, keep the cabinet off the ground, perched on a row of bricks or cinder blocks. You should also check all pesticide labels - they may have important storage information on them such as "do not store this product below 32 degrees" or "keep this product away from direct light". Keep pesticides in the original packaging, if possible. It is also a good idea to double bag pesticides. If original packaging becomes damaged or illegible, carefully repackage the material and hand write a new label. Finally, if you have old chemicals that are no longer needed, contact your local municipality and make arrangements for a proper and safe disposal.

image of a ladybug     Are deer a problem in the garden? This is the time of year when deer are on the move. Deer mate around this time of the year, and they are more noticeable during the mid to late fall. Deer damage comes in two forms : 'deer browse', and 'deer rub'. Deer browse is the result of feeding on foliage. Deer rub is the damage males do when they rub their antlers against soft, young woody branches. There are several courses of action you can take when trying to mitigate your deer dilemma. The best way to keep deer away is to erect a mechanical barrier. An 8 foot fence should do the job. If this is not feasible or cost effective, you can go with an electric fence. If you choose an electric fence, be sure to have it installed by professionals who know how to manage deer. The last option is the use of deer repellents. There are a number of products available; do an online search or check with your local extension service to find out what works best in your area. The problem with repellents is that they often need to be re-applied after rainfall. Human hair has also been known to be effective in repelling deer. You may trying hanging small bags of hair at regular intervals at the periphery of your property. Soap also appears to work fairly well as a repellent - use the same way as you would hair.

image of a ladybug     Now is the time to wrap your shrubs with twine for the winter. The branches of plants like boxwood, arborvitae and columnar junipers are susceptible to splaying or breaking under the weight of snow and ice. Secure the twine to the bottom of the trunk and wrap it upward in a spiral form. After reaching the top of the shrub, begin wrapping downward in the same spiral pattern until you reach the starting point. Finish by tying the twine securely to the trunk. Twine should be removed as soon as the threat of ice and snow has passed.

image of a ladybug     Practice good sanitation in the garden, but don't make a clean sweep. Remove senescent vegetables and bedding plants. Rake excess leaves and debris, but don't leave the ground totally bare. A scant covering of leaves will provide a natural mulch and help to insulate plant roots from temperature extremes and desiccation from cold winter winds.

image of a ladybug    Autumn is a great time to do a little clean-up for your garden tools. Wash heavily soiled shovels, rakes etc. outside and store indoors for the winter. More delicate tools such as pruning shears and hand saws should be lightly oiled after cleaning. Soak plastic and terra cotta pots in a 5% bleach solution and stack neatly in a clean and dry place, preferably off the ground. Winter is tough on clay pots; freezing and thawing temperatures often crack clay pots that are not stored dry.

image of a ladybug    Fall is a great time to add to your compost pile. Leaves, clippings, cut-backs and other brush should be layered with soil, and turned about every 4 to 6 weeks. Organic waste from the kitchen should be composted, not discarded in the garbage. Banana peels, coffee grounds, potato skins and the like help to round out a compost site. It is best to bury kitchen waste to minimize animal foraging for food.

Pest Management Tips Home

The best way to manage pests is to use a combination of chemical and non-chemical control. Only take action when the problem is serious enough to damage the plant. If we all use Integrated Pest Management (IPM), we can control pests in an environmentally conscious manner.

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Last Updated   June 11, 2009 2:53 PM

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