Think cold weather protection

Last Sunday, while checking the weather forecast in the Mail Tribune for the coming week, I noticed some of the record lows for this time of year were in the below-zero range. Certainly these were all-time lows, but having happened once, they could clearly happen again — or even get worse. It started me thinking about strategies for dealing with these types of severe cold spells, and I realized that I was not very well prepared.

Several methods can be employed to protect plants from damage associated with freezing temperatures. One of the easiest and most effective ways is to apply mulch to a depth of 3 inches over the root zones of susceptible plants. While this is a fantastic way to help your plants, it is only effective if it is done before the cold weather arrives and the mulch is in place. This means you may not have time to mulch your landscape if you hear of a severe freeze coming in the next 24 hours and you've got to work tomorrow.

Bark, straw, sawdust, peat moss, leaves and even grass clippings are common mulching materials. Keep the mulch an inch or two away from the trunk or main stem of the trees and shrubs. There are exceptions, such as roses and cane berries, where the mulch is actually mounded over the canes. Then when spring arrives, after all danger of frost has passed, these mulching materials are pulled away from the stems.

Once mulch has been applied, keep a close eye on the moisture level of the soil under the bark. Plants located under the overhang of a roof or under tall, sheltering evergreens may need to be watered during the winter months if rainfall doesn't reach them. Twice this autumn I have been surprised at how dry the soil has been under tall deciduous trees, even after a couple of rainy spells. Plants growing in dry soil are more prone to freeze damage than those whose roots are moist. This is the best argument for keeping a frost-proof hydrant open all winter.

Another effective method of protecting individual plants is by covering them with material to shelter them from freezing temperatures. Rhododendrons, camellias, azaleas and early flowering plants will often benefit from being covered with some type of cloth during extremely cold weather. Drive stakes just beyond the spread of the branches, over which you drape the cloth. Do not use plastic for this job. If left on during a sunny day, the temperature will rise too quickly under the oxygen-depriving polyethylene and damage or even kill the plant. Loosely bind long, floppy branches with soft twine before covering, if necessary. Any type of covering should be left in place only during the cold spell. As soon as the weather moderates or it begins to rain, remove the covering. However, leave the stakes, in case it gets cold again. Burlap, old moving blankets, sheets, Reemay or similar cloth or fabric materials are the best types to use as a cover over plants.

Container plants require special attention during prolonged or severe cold. Since they are exposed on all four sides, plus the top and bottom, the entire root ball may easily freeze and the container may be damaged by the expanding soil. One of the easiest ways to protect planted containers is to move them into a garage or unheated room until the danger of severe cold is over. If you lack a suitable structure, you can mulch around the sides of the container. This task is made much simpler if you have a larger container in which to place your planted one. Then you can simply pour bark or sawdust or other insulation into the larger pot until it is filled around the sides of the pot. Cover the top of the soil with more insulation. In lieu of this, wrap the container with blankets or packing. While not attractive, it will provide degrees of protection and can save a valuable plant from an untimely end. This is the time of the year when preparedness and close attention to the weather forecast can help save your plants.

Stan Mapolski, aka The Rogue Gardener, can be heard from 9-11 a.m. Sunday mornings on KMED 1440 AM and seen in periodic gardening segments for KTVL Channel 10 News. Reach him at

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