Just after the winter solstice when the daylight is at its shortest, the weather at its coldest, and the gardens smooth and barren, seed catalogs begin to arrive. I study them voraciously, just itching to settle seeds in soil. I long for something green and young and hopeful to feast my eyes upon and nurture gently, to hurry the advent of springtime’s light, energy, and taste.
I was delighted to discover a method of seed sowing that satisfied my garden yearnings without stacking much time or money on my already-busy life. Winter sowing is a method of starting seeds outdoors long before winter has loosened its grip and nighttime frosts are past. All one needs to craft a mini greenhouse is an empty plastic milk jug or similar container, potting mix, duct tape, and seeds. Cold-hardy seedlings will thrive there in the bright sunshine and swinging temperatures of late winter and early spring.
Throughout late fall and early winter, I collect empty plastic jugs such as milk and juice jugs. Anything that lets light through will do. The seeds will not be choosy, although a larger size will allow for more soil in the bottom, which little seedlings appreciate. On a cold winter day (or maybe one where the sun shines and a warm breeze tantalizes), I gather up my collection and indulge in sowing seeds.
Several things need to be done to prepare the jugs for planting. The bottom of the jug needs drainage holes bored into it. This can be done by melting holes with a heated screwdriver or puncturing slits with a sharp knife. Holes can also be made in the top of the jug for ventilation and watering, but I have found the open lid to be enough. Then the jug needs to be cut around its middle, leaving about an inch uncut for a hinge. It works best to locate the hinge just under the handle. Open the jug, fill the bottom with premoistened potting soil, and the jug is prepped for planting.
Now comes the exciting part of opening a packet of seeds, shaking them out into the palm of your hand, and sprinkling them onto the soil. Sow the seeds according to the directions usually given on the back of the seed packet. Gently press them down to make sure they get good contact with the soil, and cover to the recommended depth. I like to cover my seeds with sprinkles of vermiculite, but ordinary potting soil will do just fine. Water well. A spray bottle works well to water gently, keeping seeds from washing out of place.
Once the seeds are watered in, flip the jug shut and carefully tape it closed with duct tape. I have wound tape all the way around the jug or simply taped the sides with vertical strips of tape. Either way will work, but if you need to move your jugs frequently, the “all the way around” method will likely be sturdier.
Label well. This is important, because you do not want to end up with dozens of unidentified seedlings two months later. I use a permanent marker, which fades over time in the sunshine. A paint pen would likely be a better option.
Prepped, sown, taped, and labeled, the jugs are ready to be placed outdoors to marinate in the weather and slowly sprout and grow as nature dictates. I like to put my jugs in a sheltered, sunny flower bed next to my porch in neat rows.
Check them frequently. If the jugs are in a sunny place and there is not much precipitation, they will quickly dry out in warmer weather. When they are getting dry, set them in a pan of water for several minutes or until the water has soaked up into the potting mix.
When the seedlings have sprouted and grown several inches, untape and open the jugs and let the air rustle them a day or two before gently teasing the roots apart and transplanting into the garden. Seedlings can also be potted and allowed to grow outdoors for a while before transplanting into the garden. This will give the plant a beefier root system and an easier establishment. Keep the transplants watered well until established.
Seeds that make good candidates for winter sowing are cold-hardy annuals, vegetables, and herbs such as snapdragons, alyssum, and poppies; broccoli, lettuces, and other greens; and parsley and thyme. Many perennials can also be winter sown, like echinacea, bee balm, hyssops, painted daisies, lupine, and coreopsis. When choosing seeds, look for terms like “cold hardy,” “sow in early spring as soon as soil can be worked,” and “chill seeds before sowing.” These seeds will thrive in the volatile weather of late winter and early spring.
It is surprising how quickly those seeds sprout in their little mini greenhouses and reach for the sun. I like to keep my jugs at a convenient location where I can keep tabs on their progress and water them easily. These jugs of seedlings draw me like a magnet and I check them often, sometimes several times a day, relishing the fresh green beauty of each new sprout and marveling over the tenacity of these tiny plants on a fierce March morning. Crunching into that first garden salad and snipping that first flower bud are rewards well worth the little bit of seed sowing in the dead of winter.