Effects of Winter on Shrubs

• Excessive cold or winds can kill back shrub twigs and branches.Winter scenery with rose hips image by Le Velling from Fotolia.com
  
  Even though plants become dormant in winter, the plant still remains alive. It's vital that tissues, from roots to twigs or leaves, do not dry out during the winter dormancy, regardless of the extent of subfreezing temperatures. Dry soil kills roots when accompanied by cold. Excessive cold ruptures plant cells in twigs, buds or leaves to cause drying, browning and death. Drying winds also dry out tissues not protected by natural waxy coatings. Excessively heavy snow or thick ice can break twigs on shrubs. Foraging animals also can destroy dormant shrubs, especially in mid to late winter when other food sources are depleted.
  
  

Protection Implements

• Snow is an inexpensive natural insulation for plants in winter. If you're fortunate to live in a region with reliable winter snowcover, use it. A shrub covered in snow that doesn't break its branches is protected from temperature swings, exposure to drying wind and sun, and the reach of hungry animal mouths. If snow is lacking, gardeners can construct small wood structures over or to the side of shrubs to shield them from winds, animals or undesirable exposures to sunlight. Cardboard, burlap, black plastic, wire mesh and thick layers of mulch all can be employed to insulate shrubs from overwintering threats.
  
  

Caveats

• Broadleaf evergreens have more surface area that quickly desiccates in winter.frost image by Maciej Syrek from Fotolia.com
  
  Gardeners must consider long-term plant health when installing and relying on winter protection materials. If the soil never freezes, access is needed to water the soil to keep plants alive in mild winter regions. Plants with evergreen leaves, broadleaf or needles, still need light to remain alive. When temperatures are favorable, even on mild winter days, some photosynthesis occurs. Air circulation prevents condensation and rot. When shielding plants from drying winds or sunlight, they need to orient the screen or wrapping to fully block the threat. Structures must also be sturdy so snowdrifts, heaving soil or whipping winds don't collapse the devices.
  
  

Continue to Monitor

• Snow makes an excellent insulation for shrubs, but must not bend branches too much.shrub image by Henryk Olszewski from Fotolia.com
  
  Once wrappings, screens or mulch are used to protect prized shrubs in winter, the gardener cannot abandon monitoring. Before and after storms, check to make sure the plant is still protected. Items may have shifted or broken, or may not be performing as you had hoped. Frequent monitoring allows you to make changes to improve plant survival, including shaking off heavy show from evergreens that may lead to branches breaking. It's also important to promptly remove winter protective devices in late winter. You want plants to gradually experience natural soil and air warming in spring and leave dormancy with little stress.