How to Extend the Vegetable Growing Season


Adding a few weeks on to either end of the growing season can increase the yield of your vegetable garden and allow northern gardeners to experiment with longer-season varieties. In the coldest climates, gardeners can take advantage of season-stretching techniques, setting plants out earlier and harvesting long past the first frost. Combine cold-hardy vegetables like broccoli and cauliflower with frost-protected tomatoes and eggplants for the longest---and most productive---growing season possible.

Step 1

Use water-filled rings. Available in garden supply stores and catalogs, these cone-shaped, water filled tepees surrounds a single plant. As the water inside the tepee freezes, it releases heat and protects the plant. These are used early in the growing season to protect small, immature plants.

Step 2

Cover vulnerable veggies. Floating row covers are lightweight fabric sheets that protect from frost and wind. According to Colorado State University Extension, they provide 2 to 4 degrees of additional frost protection.

Step 3

Create a heat tunnel. Install hoops at 3 to 5 foot intervals in the garden bed, and protect several plants at once. Fasten plastic sheeting to the hoops. This is similar in protection to the floating row covers (2 to 4 degrees of additional frost protection) and must be removed when temperatures rise.

Step 4

Build a cold frame. Cold frames are very primitive greenhouses, and they can house and warm plants throughout the colder growing months. A simple cold frame can be made from four to six hay bales. Arrange the bales in a square or rectangle in a sunny, flat area. Add several layers of newspaper to the bottom and add your plants. Cover the frame with clear plastic, an old window or a large plastic sheet. Open the cover every day to prevent overheating. According to Colorado State University Extension, a cold frame can add 3 to 6 degrees of frost protection and two to six weeks on either end of the growing season. Covering the frame with an aluminum "space blanket" and adding a strand of C-7 medium-sized Christmas lights increased the frost protection 30 degrees.

Things You'll Need

  • Water-filled rings
  • Row covers
  • Hoops and plastic
  • Four to six hay bales
  • Plastic tarp, window frame or plastic sheet
  • Space blanket
  • C-7 medium Christmas lights


  • Colorado State Extension: Extend the Growing Season
  • Colorado State Univ. Extension: Frost Protection
Keywords: season-stretching techniques, vegetable garden, frost protection

About this Author

Moira Clune is a freelance writer who since 1991 has been writing sales and promotional materials for her own and other small businesses. In addition, she has published articles on, and