x
 
 
Learn which plants thrive in your Hardiness Zone with our new interactive map!

How to Keep Plants From Freezing in the Winter

By Barbara Fahs ; Updated September 21, 2017

Frost on the pumpkin won’t kill it, but it can kill your tomatoes, zucchini and tender summer annual flowers. It can also harm citrus trees. Some plants are meant to live for only one season—you can’t help annuals, such as marigolds, zinnias, most garden vegetables and herbs, but you can keep certain other plants from freezing in the winter by giving them shelter, moving them indoors, covering them with a tarp or plastic, and other simple methods. Subtropical plants such as bougainvillea, hibiscus and some jasmines are examples of frost-tender plants you can help.

Keeping Plants From Freezing

Bring all of your potted houseplants indoors before your first fall frost. Provide them with a sunny, warm environment—a south-facing window is often a good location. Be sure to spray them with insecticidal soap spray to prevent introducing insects into your home. Alternatively, you can move potted plants into a small hobby greenhouse.

Spray tender plants in the ground with an anti-transpirant spray. Examples of plants that you can help with this method include citrus trees of all types, especially the more tropical varieties of lime.

String outdoor Christmas lights all over your frost-tender plants. You can also hang incandescent light bulbs over and near your plants to give enough warmth to prevent freezing.

Cover your plants with clear plastic sheeting, a floating row cover (“Remay”), tarps or blankets. If you can, build a frame to support such materials because frost or freezing temperatures will damage the parts of your tree where the plastic or other material touches it.

Keep plants well watered during cold weather because freezing temperatures cause plants to become desiccated. Also spread a thick layer of mulch (compost, sawdust, leaves or wood chips) around the base of your plants to keep the soil moist and warm. Mulch is especially helpful for bulbs.

Run a sprinkler to cover your plants with below-freezing, moving water. If the water is moving, it cannot freeze, and this protects plants.

 

Things You Will Need

  • Insecticidal soap spray
  • Greenhouse (optional)
  • Anti-transpirant spray
  • Lights
  • Clear plastic sheeting
  • Floating row cover
  • Tarp or blanket
  • Garden hose/water
  • Compost
  • Sprinkler system

Tips

  • Subtropical plants such as lantana should come back from their root systems in the spring. You'll need to endure their bad looks until then, but wait until after your final frost to prune them back because the old, dead leaves and branches will help to protect the plant from more frost.
  • If you cover your plants with clear plastic or a row cover, you can leave it on all winter. Remove blankets or tarps during the daytime because they will interfere with the plant's ability to photosynthesize.
  • Choose plants that are adapted to the climate where you live. Plants that are native to your area will be able to withstand not only freezing temperatures but also droughts in the summer months.

Warning

  • Be careful of electrical shock if you use lights of any kind and then spray your plant with water.

References

About the Author

 

Barbara Fahs lives on Hawaii island, where she has created Hi'iaka's Healing Herb Garden. Fahs wrote "Super Simple Guide to Creating Hawaiian Gardens" and has been a professional writer since 1984. She contributes to "Big Island Weekly," "Ke Ola" magazine and various websites. She earned her Bachelor of Arts at University of California, Santa Barbara and her Master of Arts from San Jose State University.