How to Lengthen the Growing Season for Fall and Winter Vegetables with Cloches, Cold Frames, Greenhouses, Mulching, Floating Row Covers, and Raised Garden Beds
By Jennifer Copley (Last Updated 26 July 2011)
The following are some ways to lengthen the growing season so that you can have fresh produce throughout the fall, winter, and early spring.
Cloches (small, mobile greenhouses made from plastic or glass) trap heat while letting in light. Cloches can be simple or complex, and there are several types that can be made or purchased:
- A clear container with one or more air holes that covers a single plant (large pop bottles with their bottoms removed work well for this purpose)
- Semicircular wire hoops acting as a frame for a clear plastic roof
- A metal frame with glass panes
Slugs like cloches, so be sure to remove these garden pests regularly (see Natural Garden Slug Control for nontoxic slug and snail deterrents).
Cold frames are permanent structures that protect against strong winds and cold temperatures. Cold frames can be made using an old window that forms the slanting roof of a box (ideal dimensions are 18 inches high at the back and 12 in front). The slant enables water run-off and captures the sun’s heat well. Cold frames can also be purchased from garden supply stores and even some department and hardware stores.
Cold frames should be south-facing and ideally situated on slightly sloping ground for drainage. The top window can be opened on warm, sunny days and the cold frame insulated with heavy cloth or burlap on cold days.
You can provide even more protection against frost with a hot bed, which is a cold frame that has a heat source at its base. Today, hot beds are usually heated with electric heating cables, though the traditional method was to add approximately 1.5 feet of decomposing manure under the soil to generate heat.
Available in a broad array of designs, greenhouses don’t require heating to raise produce as they capture and store the sun’s heat so well. Greenhouses enable the production of cucumbers and tomatoes during the winter even in very far-north locations.
Adding a 1-2 inch layer of mulch insulates plants against the cold, as well as discouraging weed growth, reducing erosion, and helping the soil retain moisture during dry spells. Ideal mulch materials include bark, peat moss, and sawdust.
Bark and sawdust leach nitrogen, so this critical nutrient must be replenished in the soil before replanting. Also, it’s necessary to check under the mulch from time to time to make sure that the soil has not dried out.
Mulching is particularly beneficial for root vegetables.
Floating Row Covers
Floating row covers, typically made from lightweight clear plastic, polyester, or cheesecloth, are placed directly over seeded or transplanted areas and secured with pegs, staples, or by tucking them into the soil. These coverings are light enough that the plants are able to raise them as they grow.
Floating row covers can hold in heat, and they provide the added benefit of acting as pest deterrents. The downside is that some types of covers also reduce the amount of light reaching plants.
Raised beds, which can increase the soil temperature 8-12 degrees Fahrenheit, can be created using bricks, stone, concrete, or wood. Although not as effective as cloches, cold frames, greenhouses, and floating row covers, raised beds give a small boost in heat and provide the added advantage of reducing the need to bend over when tending to or harvesting crops.
Vegetables and Herbs That Can Be Grown During Fall and Winter
There are a number of produce plants that can be harvested throughout fall and even winter in some cases. Most of these are root vegetables and leafy greens, though there are other cold-loving vegetables as well. For lists of vegetables that grow well during the cold season, along with photos and planting time recommendations, see the Root Vegetables, Fall and Winter Vegetables, and Leafy Green Vegetables pages.
For more gardening articles, visit the main Gardening page.
- Dowding, C. (2008). Salad Leaves for All Seasons: Organic Growing from Pot to Plot. Devon, UK: Green Books Ltd.
- Ed Hume Seeds. (n.d.). “Fall and Winter Vegetable Planting Guide.” HumeSeeds.com.
- West Coast Seeds. (2011). “Crop Protection.” WestCoastSeeds.com.