Season Extension: Eating fresh food throughout the winter

Hoop house construction at the Greenside Out Garden.

Late fall is a bittersweet time in the garden. I often feel a mix of emotions - pride in the hard work and bountiful harvest of the season, relief that the garden no longer needs to be tended to so diligently, a sadness as the supply of fresh vegetables dwindles, and a determination to have an even better garden next year.

Yet even in cold Northeastern climates, the onset of winter does not have to mean the end of all fresh produce. There are several techniques for growing food during this chilly time of year. At the Greenside Out Garden, we built hoop houses (also known as low tunnels) in which we are growing arugula (that tastes delicious right now!), and we have two cold frames with kale.

Hoop house construction earlier this season.

Earlier this season I attended a Season Extension workshop offered by the Boston Naturals Area Network and, using their guidelines, we constructed four hoop houses at the Greenside Out Garden. These structures were fairly easy and inexpensive to build. For each bed, we used six ¾’’ x 1’ PVC posts, ½’’ x 6’ PVC hoops, one 4ml sheet of plastic (6’ x 12’) and one 6’ x 12’’ piece of agricultural fabric (also known as reemay). These materials will fit a 4’ x 8’ bed and most can be found at the hardware store (the PVC tubing in the plumbing section and the plastic is sold as painter’s plastic). The reemay is a bit trickier to find, but Territorial Seed Company sells different sized quantities on their online store. You can also experiment with materials! For my home garden, I built a hoop house using bicycle wheels for the hoops. The reemay and the plastic go over the hoops. To erect the hoops, first stick the wider, shorter pipes (the posts) into the soil at each corner of the bed, and two across from each other in the middle. Then, insert the hoops into the posts (one hoop per two posts).

All sorts of greens can be grown in the hoop house. Mustard greens, including arugula, can be harvested in the fall and then will grow back again in the spring. Other more cold-tolerant greens, such as kale, collards, and spinach, can be harvested throughout the winter.

There are many online resources for building hoop houses. The following how-to guide is one example: http://www.backyardgardening.net/article/raised-bed-hoop-house/ As you see, there is no one way to construct a hoop house (here the hoops are secured with pipe clips, whereas we inserted the hoops into wider tubes that were inserted into the soil). This article also gives suggestions for how to secure the plastic to the hoops.

There are many other techniques for extending the season. 
For more in-depth information check out Four Season Harvest and The Winter Harvest Handbook by Eliot Coleman.

- Marie Benkley, Garden Coordinator