Winter is here in Columbus and there’s not much green in my garden and there have been more cloudy than sunny days. It’s too cold to do much outside. Gardeners like me have gone through seed catalogs with their tempting photos or decided to change a planting area and have maybe scratched around in the mulch looking for perennial sprouts. Some of the more compulsive among us (guilty here!) have drawn out our plan for spring plantings on graph paper. Gardeners may wait for a rose to bloom or that first tomato to ripen, but some, like me, are pretty impatient for planting time to come.
Winter sowing may be the cure for a gardener’s blues. Intrepid gardeners have been sowing seeds in January for a few years now. Trudi Davidhoff used the term “winter sowing” about 30 years ago and the method has become more popular in the last few years. The definition that’s been adopted by the USDA follows: ” A propagation method used throughout the winter where the temperate climate seeds are sown in protective vented containers and placed outdoors to foster a naturally timed, high percentage germination of climate tolerant seedlings.” In spite of this rather dry description, the method lets gardeners get their hands in the soil and plant and not wait the typical six to eight weeks before the last frost. It’s also fun to check to see what seedlings might have popped up.
Winter sowing offers a home gardener several advantages over the more traditional lights and peat pots in the basement or on a sunny windowsill. Our seeds are less at risk of being blown or washed away, being eaten or rotting in too damp soil than if sown directly in the soil in autumn. It saves energy and resources — human and otherwise. Since the containers are outdoors, no plant lights are needed, and no heat pads for the seedling trays equals electricity saved. Stratification, a period of cold some seeds need to break dormancy, occurs naturally outdoors without worry of mildew or being too moist in the back of the fridge. Reusing milk cartons, juice bottles or plastic tub salad containers eliminates the need for purchasing plastic trays and pots. Since this method requires no transplanting into larger pots or hardening off, there’s less work for the gardener. No more lugging trays of plants outdoors on warm sunny days and bringing them back indoors in the evening to harden them off toward the end of April.
The process is simple and the materials needed are few and easy to obtain. The containers mentioned previously are the most common and allow light to reach the seeds. If the container is safe for food, it is safe for your seeds.
Cut the washed container around the middle leaving a hinge. Pierce the bottom in a few places for drainage. Containers like the salad boxes also need a few holes for ventilation on the top as well. With milk and juice jugs, keeping the lid off serves that function. Add three to four inches of good quality potting soil that has been well dampened but not soggy. Several sources indicated that is important to use potting soil rather than a soilless mix. Because the seedings will not be transplanted, they’ll need nutrients that the soilless mixture lacks. If slugs are a problem in your area, landscape cloth, a coffee filter or even newspaper will prevent them from entering the container through the bottom when put in before the soil.
The spacing for sowing seeds varies and a few methods allow for this. Seeds like leaf lettuce can be sown somewhat thickly anticipating planting them out in clumps or rows. It’s desirable to have seedlings like peppers or tomatoes more separated so short sections of paper towel tubes can be inserted into the soil making individual planting spaces for two or three seeds. Cover the seeds as directed on the packet. Most sources recommended labeling your containers on the inside and the outside in case the outer one weathers away. Close the containers and seal with duct or packing tape and place in a sunny spot outdoors. The location should be sheltered from the wind, but not under eaves or a porch that is shaded. Mine did well against the east side of a short garden wall last spring. Winter rain and snow will often provide enough moisture, but check occasionally and if the soil is dry, add a little water.
Some “winter sowers” use the December solstice as a target date for planting, but getting things going in the next few weeks should be OK too. Native plants and grasses, as well as cool weather crops like spinach, can be set out now. Later in March, spring vegetables like bok choy and broccoli can go out. Herbs basil and cilantro, zinnias, cosmos and similar annuals can be started then, too. Save April for setting out containers of the peppers, tomatoes and others that love the warmer weather.
A few days before setting out the beautiful seedlings, open the containers during the day, and close at night if the temperatures warrant. Transplant them at the usual time and enjoy the fruits of reduced labor. I had some winter sown seeds do extremely well and some not. In the end, gardeners are optimists and gamblers, so forge ahead and keep planting, wishing for a better outcome next time and hoping for that first bite of the perfect red sun-ripe tomato!
Emily Baker is a Purdue Extension master gardener and has been gardening nearly 50 years. She is member and past president of South Central Indiana Master Gardener Association. More information about the association is available at scimga.org. Sources for this article include University of Maryland Extension, Penn State Extension and University of New Hampshire. Send comments to therepublic.com.
