Want to enjoy fresh salads of lettuces, spinach and other leafy greens picked from your garden this winter? Home gardeners, even in northern states, can grow these and other cold-hardy vegetables outdoors throughout the winter under inexpensive row covers draped over a simple hoop framework.
Row covers are made of lightweight fabrics available in a variety of cold-protection strengths. Double or even triple layering may be needed in some areas for continual winter harvest. Rain and sun still reach the plants because the fabric is permeable, although sunlight will be reduced by the degree of cold-protection of the fabric and the layers used. Be careful if you use plastic. It doesn’t allow in air or water and may cause overheating.
The primary benefit of row covers is they create a greenhouse effect that traps heat and raises day and night soil temperatures, which extends the growing season. Row covers also:
Keep soil moist
Prevent wind damage
Deter foraging animals
Install quickly and are economical
Allow for easy harvesting
Where to find
Ask for row covers at organic gardening centers or agriculture supply centers or search online. The fabric comes in several widths, can be cut to fit any length of row and is inexpensive to ship in quantities needed by most home gardeners. Be sure to allow for the height of the hoop when purchasing your fabric. For an eight-foot row, the fabric needs to be at least 12 feet long.
How to install
The idea is to create a tunnel. This is easily accomplished by installing hoops, draping the fabric snugly over them and securing it to the ground.
The simplest way to create the hoops is to use thin, flexible wire usually available where you purchased the fabric. Simply push an end of the wire into the ground on one side of the row, loop it to the other side and push that end into the ground. For a standard 4x8 foot plot, four hoops should be sufficient.
To create a more substantial hoop, use one-half-inch PVC pipe. This is available from hardware or box stores and comes in 10-foot lengths. Use this length or cut it to eight feet, depending on the height of the crop you are covering. To secure the PVC pipe, hammer a smaller size of PVC pipe or rebar into the ground on both sides of the plot, leaving six inches above the ground. Place the long PVC pipe over the smaller one or the rebar.
In either case, the hoop can be removed in the spring.
If you use a wooden planting frame and want a permanent hoop for other seasons, summer shading for instance, fasten the PVC pipe to the outside of the frame with clamps.
Drape the fabric over the hoops and secure it to the ground so it doesn’t come loose and expose vegetables to winter elements. Hold the fabric in place with plastic stakes available from garden centers or with anything that’s handy – rocks, two-by-fours, metal pipes.
What to cover
Cooking and salad greens will need to be covered in most areas for continual harvest. Onions, garlic and herbs usually aren’t covered. For other vegetables, check your hardiness zone.
Simply raise the fabric enough to harvest and re-secure it.
Row covers have varying life spans and can be repurposed by:
Placing them over newly seeded lawns to prevent erosion
Laying them under mulch as a weed barrier
Covering annuals to protect against frost in spring or fall
Got other tips for winter gardening or row covers? Leave us a note in the comments below.
Photos: Tom Oder