Chelsea Green Publishing

Chelsea Green Blog

Get a Jump on the Planting Season: Build Your Own Cold Frame, Part 2

Yesterday we introduced you to cold-frame gardening—an easy and fun way to extend your growing season through the winter. Today we’ll dig in to building the actual cold-frame box. Tomorrow, we’ll show you how to top it off with the cold-frame light.

The following is an excerpt from Four-Season Harvest: Organic Vegetables From Your Garden All Year Long by Eliot Coleman. It has been adapted for the Web.

The Cold Frame Box

Any cold frame design that protects plants will serve you well. To be enjoyable to use, however, the design must be simple, attractive, pleasant to work with, and dependable. Having tried them all, we settled on the traditional design. The simplest cold frame is a rectangular wooden box, 8 feet long and 4 feet front to back, with a slight slope to the south. We build them out of 2-inch lumber to make them strong, but 1-inch stock would be adequate. Three 8-foot boards are necessary: two boards 12 inches wide and one board 8 inches wide. One of the 12-inch-wide boards is used for the back wall. The 8-inch-wide board is used for the front wall. The second 12-inch board is cut into two 4-foot pieces, which are each cut diagonally lengthwise so that they are 8 inches wide at one end and 12 inches wide at the other.

It is easiest to put the frame together with the boards sitting on a flat surface and the diagonal cut edge of the side walls facing up. When you do this, you will notice that the bottom edge of the frame is flat, whereas the upper edge has a slight discontinuity where the diagonal cut meets the front and back walls. In order for the lights to sit on the flattest surface, you should turn the frame over before using it. Any discontinuity of the other edge is then hidden by contact with the soil. The frame will slant slightly to the south, allowing more light to enter.

Attach a 4-foot-long 2×2 to what is now the top. This piece extends across the middle of the frame, running front to back. You will want to cut notches in the top of the front and back walls so this cross piece sits flush with the top. (See drawing.) This helps keep the sides spaced and also provides a handle that one person can use to lift the empty frame and carry it to a new location. If you use 1-inch wood, you might want to place more of these stiffeners across the frame.

We use standard pine or spruce for our frames. We purposely do not use treated wood, nor do we treat the frames with a preservative. Even the supposedly safe products should not be used in close proximity to food crops. Wood rots where it is in contact with the earth, however, so we attach a strip of scrap wood about 1 inch thick to the bottom edge of the frame where it touches the soil. In a few years, when this strip begins to rot, we replace it with another. The rest of the untreated wood frame will last for many years.

We also do not paint the frame. Yes, if the interior were white, it might reflect a little more light than the gray weathered wood, but paint is just one more complication. Rather than having to scrape and paint every few years, it’s best to keep things simple.

Tune in tomorrow for the third and final installment of “Build Your Own Cold Frame”: The Cold Frame Light.

Photo courtesy of Homegrowers Exchange.


Tips on No-Till Farming and Cover Crops

In the below Q&A, author and permaculture designer Shawn Jadrnicek answers questions about no-till farming and the use of cover crops from two readers (one from North Carolina, and the other from Nova Scotia). In his groundbreaking book, The Bio-Integrated Farm, Jadrnicek provides in-depth information on water flow management along with projects that use the free forces of nature—gravity, […] Read More

Reimagining Restoration as a Radical Act

Finding ways to manage “invasive” species as we’ve come to know them has sparked a vigorous debate within conservation and restoration communities, as well as farmers, gardeners, and permaculturalists.In her thought-provoking book Beyond the War on Invasive Species, author Tao Orion urges us to rethink and reimagine restoration as a way to break out of […] Read More

What Can Wisteria Do For Your Forest Garden?

Jerome Osentowski, founder of the Central Rocky Mountain Permaculture Institute (CRMPI) in Basalt, Colorado, is one of North America’s most accomplished permaculture designers and author of the new groundbreaking book, The Forest Garden Greenhouse. Part case-study of CRMPI’s innovative greenhouses and part how-to primer, Osentowski’s book shows that bringing the forest garden indoors is possible, even on […] Read More

Tips on Perennial Crops with Eric Toensmeier

Eric Toensmeier is the award-winning author of Perennial Vegetables, Paradise Lot, and most recently The Carbon Farming Solution—a groundbreaking new book that treats agriculture as an important part of the climate change solution, rather than a global contributor to the problem. As part of our “Ask the Expert” series going on throughout the month of May to celebrate […] Read More

How to Design Swales for Optimum Water Flow

May has arrived! The birds are chirping, flowers are budding, and it’s time to officially celebrate Permaculture Month.Throughout the next few weeks, we are putting our pioneering permaculture authors to work for you in our “Ask the Experts” series. If you are looking to become a better permaculturalist, there’s still time to participate. Submit your questions here.Today’s topic is […] Read More
Follow us
Get every new post delivered to your inbox
Join millions of other followers
Powered By WPFruits.com