This article appeared in the January-February 2002 issue of Horticulture Update,
edited by Dr. Douglas F. Welsh, and produced by Extension Horticulture,
Texas Cooperative Extension, The Texas A&M University System, College Station, Texas.

Helping Your Plants To Overwinter:
12 Steps To Take

inter is definitely here, and it's wise to know what actions you should take to ensure plant survival. Keep your winter worries to a minimum with this handy clip-and-save list from the American Nursery & Landscape Association (ANLA):
  1. Make sure plants are healthy going into winter. Some varieties benefit from one last feeding. Consult a nursery professional to determine which plants in your landscape need this type of attention.

  2. Check for pests. Many insects--like aphids and lacewings feed until the first hard freeze. Pest infestations can force plants into an early dormancy that decreases winter survival.

  3. Mulching protects roots and conserves moisture. One to two inches of bark, or three inches of pinestraw or leaves under the canopy of a plant protect it from sudden changes in temperature and soil moisture.

  4. Continue watering if necessary. Outdoor plants need water, even when they aren't actively growing. Periods of extended drought make plants more susceptible to cold injury. Watering up to one inch per week is recommended during dry spells.

  5. Avoid pruning within six weeks of the average first frost date. Late fall pruning can result in new growth that does not have time to harden off before winter.

  6. Provide extra protection during hard freezes. Cover your most cold-sensitive shrubs with old blankets. If you use plastic, don't let it touch leaves, because it conducts cold that can harm extremities.

  7. Take a wait and see approach with plants that seem to have died from a freeze. They may return to life in spring. If so, prune any dead tips or branches back to just above the new growth.

  8. Container Plants: Again, make sure plants are healthy going into winter. Check for pests and treat if necessary. Reduce the frequency and strength of fertilization during winter and for plants that are not actively growing. Water-soluble or slow-release fertilizers are preferable.

  9. The heating systems in most homes tend to decrease humidity levels. Supplemental mistings or changing the location of plants can improve health.

  10. Most plants tolerate a few months of lower light levels while overwintering. But do check plants occasionally--look for symptoms of light deprivation. These include yellowing or pale foliage, dropping or drooping leaves, and leggy growth. If necessary, move to an area with higher light levels or supplement with grow lights. Your garden center can offer advice for dealing with this problem.

  11. Take it easy when reintroducing plants to the great outdoors. Sunburn of foliage commonly occurs when plants are brought into intense light too quickly. After all danger of frost has passed, acclimate overwintered plants gradually. Give them a few days in an intermediate zone, like a covered porch or under a tree canopy, before moving into full sun.

  12. Spring is a good time to see if plants are potbound. Are plants wilting, do they have poor color, are leaves dropping? Lay the pot on its side and gently tap it out of its pot. Are the roots crowded, or even growing through drainage holes? If so, it's time to repot. Your garden center is a great source of colorful and practical containers, as well as potting soil mixes and fertilizers. Those items, and these overwintering suggestions, are about all your plant needs to look great going into spring.