Cold temperatures don't have to mean the end of the growing season
Now that fall has finally arrived here in Western Pennsylvania, the nighttime temperatures are dipping below freezing. If you're like many vegetable gardeners and you still have crops growing in your garden, it's time to consider ways to extend your harvest for a few more weeks. Thankfully, there are several season extending tools available for home gardeners that are both cost effective and simple to implement.
Cloches: A cloche is a small glass or plastic “globe” that's used to form a mini-greenhouse over an individual plant. Cloches protect plants from light frosts, both early and late in the season. But because cloches are typically on the small side, they work best on smaller plants; you won't be able to cover a full grown tomato plant with a cloche. However, cloches can be very useful in allowing gardeners to continue to harvest late season plantings of globe basil, lettuce and many other small-statured plants for a few weeks to come. You can buy commercially made cloches or make your own from household items. I make cloches out of translucent milk jugs with the bottoms cut out of them to cover baby kale, chard and other greens in the autumn. I also sometimes use glass Mason jars to cover tender plants from early fall frosts. Just remember to remove the cloches on warm days; otherwise you could “fry” the plants housed inside. I was able to grow a delicious green called corn mache all winter long last year, simply by covering each plant with a milk jug cloche.
Row covers: This translucent fabric is laid over plant tops, protecting them from cold nighttime temperatures. Depending on the thickness of the row cover you purchase, this fabric can protect plants down to 25 degrees, extending the harvest of the plants kept snug under its blanket. I use row cover to shield late plantings of zucchini, as well as peppers and eggplants, from the first few fall frosts. Doing so often allows me to continue to harvest for several more weeks. Row cover also comes in handy when protecting tropical patio plants from light frosts.
Cold frames: These structures are made from materials such as wood, concrete block or straw bales. A frame is constructed and then covered with a glass or acrylic “window” on top to allow the sun to reach the plants housed inside. Cold frames are often oriented for maximum sun exposure during the colder months of the year. High-quality cold frames allow you to grow greens, radishes and other cold-tolerant crops throughout most of the winter, even when the frame is covered with a layer of snow. You can purchase commercially made cold frames or build your own from one of the many DIY plans found on the Internet. Cold frames can be built right over plants already growing in your garden or they can be placed in a vacant area of the garden and then sown with seeds of cold-tolerant crops for fall and winter harvests.
Mini hoop tunnels: This is one of my favorite ways to protect vegetable crops from fall frosts. Mini hoop tunnels only take a few minutes to construct, and they offer good protection for the plants housed underneath them. I often build mini tunnels over existing planted garden beds by creating several arches of 1⁄4” PVC pipe down the length of each garden bed. The ends of each PVC pipe are either secured to a length of rebar hammered into the ground, or fastened securely to the outside of a raised bed frame using a two-hole pole bracket. Then, I cover the PVC arches with a sheet of 6 mil clear plastic and pin the plastic to the ground with rocks and bricks to hold it in place. A double layer of plastic offers even more protection. This is a great way to turn a raised bed into a mini greenhouse for the winter. Though it won't protect plants once the temperatures dip well below freezing, mini hoop tunnels do extend the season by several weeks, if not months. It works particularly well to insulate carrots, beets and other root crops.
Horticulturist Jessica Walliser co-hosts “The Organic Gardeners” at 7 a.m. Sundays on KDKA Radio with Doug Oster. She is the author of several gardening books, including “Attracting Beneficial Bugs to Your Garden: A Natural Approach to Pest Control” and “Good Bug, Bad Bug.” Her website is jessicawalliser.com. Send your gardening or landscaping questions to firstname.lastname@example.org or The Good Earth, 622 Cabin Hill Drive, Greensburg, PA 15601.