Mid-winter produce. Yuck. Carboard-y tomatoes, small, expensive heads of lettuce and bunches of greens, and fruit from half-way around the world. Not very healthy, appetizing, or eco-friendly.
Have you ever considered growing food year round? With a winter garden, you can have the control over your diet you enjoy in summer. You can eat fresh, tasty, nutritious, organic foods of your choice!
Growing methods for winter gardening
Your climate will determine the best way to grow a winter garden. In the northern US, some sort of cover is necessary to insulate the plants from frost and snow. IN the southern US, cool weather crops can be grown outside in a regular bed. In Tucson, I have grown cool weather greens (spinach, kale, chard, etc.) in a raised bed in the back yard all winter. That was quite a treat!
Cold frames for growing produce in cooler months
The best way to grow in winter is to build simple cold frames. I have done this out of scrap wood and old windows, so it does not need to be a huge expense. Decide on the size, then make the back 6” higher than the front. Decide on a height when you decide on what to plant. Greens and lettuce are not tall, but you can grow broccoli and fava beans in a taller cold frame.
Cut the sides to fit. On the high side, attach an old window with a couple of hinges. You may want to have a latch on the south side if you think the wind might blow it open, or if critters might be able to get in.
The slope of your cold frames should face south to gain the most winter sun. If you can place them on the south side of your house or an outbuilding, the environment will be warmer and good for plant growth. The plants will be better insulated if you bury the frames in the ground about 4-6”. You can also put rigid foam insulation around the outside of the frames.
On very cold nights, you will want to cover them with old blankets. You can make a hotbed by running electric cable beneath the soil. The more natural and eco-friendly way, though, is to put about 1.5’ of fresh manure beneath the soil. As it decomposes, it releases heat, keeping the plants warm. You will want to remove snow from the tops of the frames so the plants can get sunlight.
Plants for Winter Gardens
Since you can never duplicate the heat of summer, you need to grow cool weather crops. The best plants for winter cold frames and solar pods are:
- Swiss Chard
- Collard greens
- Fava beans
Solar pods for winter gardening
I learned about this winter growing method when I went to school at the University of New Hampshire for plant science. Our soils teacher took us on a field trip to Solar Survival, the home and lab of Leandre and Gretchen Poisson, authors of Solar Gardening: Growing Vegetables Year-Round the American Intensive Way. They grew food all winter in frigid, frozen, snowed-in northern New England using solar pods, which they developed.
A solar pod is a 4′x8′ cold frame surrounded on the outside with rigid foam insulation and buried partially in the ground. The lid is an arch of two layers of Kalwall® greenhouse glazing with Angel Hair, a fine and translucent, yet heavy duty, insulation, sandwiched in between.
The thermal mass inside the pod is a black 55-gallon drum filled with water and laid on its side at the north end. During the day, the water absorbs the sun’s heat and slowly radiates it back out over night keeping the plants and soil warm.
I wrote about this on my own blog as part of a series on how I learned about solar energy.
The Poissons also developed the solar cone, which is a single layer of Kallwall® glazing rolled into a large cone shape to cover one plant. This is good for a row of cool weather plants, such as greens.
You can see the pods, cones and Leandre Poisson in these photos.
Winter gardening maintenance
Winter gardens do not need fertilizer. Be sure to use good soil with compost and/or manure. Plants do not need as much water, either, maybe just once a week, but be sure to check for dryness before watering. Overwatering is the main reason for winter gardening failure.
Winter gardening takes some planning. Plant before your first killing frost, so the plants are somewhat mature before it gets cold. Find out from your county extension your average first frost date. Seed companies send out fall planting catalogs in July. The seeds offered are specifically for fall and winter growing, so that is what you should buy and plant.
It’s not to late to start planting now, but you will have to move quickly! It will be worth it, though, when you are harvesting fresh lettuce in December or January!