By Katie Ruffe
Annual seedlings started using the author’s methods
As tariffs, climate change, and supply chain disruptions drive up grocery costs—and as research continues to highlight the health impacts of our industrialized food system—more people are becoming motivated to grow their own food. Starting this journey, however, can feel daunting. A basic internet search often yields overwhelming lists of expensive tools and supplies. While growing from seed is cost-effective, the initial investment of time and money required for indoor seed-starting can be off-putting. Luckily, the “winter sowing” method allows you to start seeds with almost as little time, money, and waste as it takes for a seed to sprout on a forest floor.
To begin winter sowing, you only need nutrient-dense potting soil, seeds, water-resistant tape (such as duct tape), and an enclosed, light-permeable container with drainage holes. The best containers are clear or opaque gallon or half-gallon milk and juice jugs, washed and rinsed thoroughly. I’ve also had success upcycling deli trays, salad greens containers, and bulk vinegar jugs. Whatever you choose, ensure the container has drainage holes at the bottom.
Since the tops must be accessible, cut the top half off any container that doesn’t have a lid; I like to leave a small section attached to act as a hinge. Fill the bottom 3 inches with moist (but not dripping) potting soil and sow your seeds as you would in flats or plug trays. Finally, use duct tape to seal the jugs or replace the lids. Jugs are ideal because they have built-in ventilation—just leave the cap off! If your container doesn’t have an opening, poke a few holes in the lid to allow for air exchange while still retaining heat. I save old jugs and food containers all year for this, but don’t worry if you haven’t. Most local coffee shops and cafes will give you their recycling instead of tossing it. Don’t forget to label your containers!
Seeds germinate outdoors in recycled milk jugs.
Place your sown seeds outside in a south-facing spot where they will receive full sun and minimal wind. You can set them on a porch, a stoop, or directly on the ground. To prevent them from tipping over, try tying them together in a cluster. Check on them periodically to ensure the soil remains moist and the environment stays humid; the interior walls should look foggy or be beaded with moisture. Leave them uncovered through snow and rain, since this will replace lost moisture. These containers act as mini-greenhouses, insulating the seeds and creating a warmer microclimate than they would experience in the wild.
The timing is flexible, but a good rule of thumb is to wait until after the winter solstice so the days are getting longer. For cold-hardy plants that you can transplant before the last frost, such as brassicas and root vegetables, don’t wait until spring to set them out. Similarly, seeds that need a period of “cold stratification”, such as native perennials, need a few weeks of cold to mimic nature’s rhythm. Conversely, if you are growing warm-weather crops, such as tomatoes, peppers, and squash, wait until spring—or at least until temperatures are steadily increasing rather than fluctuating wildly—before sowing.
Once seedlings emerge, it is important to “baby” them. Protect them from unseasonably high temperatures by lifting the tops during the day and replacing them at dusk. On freezing nights, you can replace jug caps or provide extra insulation; I usually throw a moving blanket over mine until morning. That is the extent of the attention they need until they are ready for the ground. Best of all, these plants are already “hardened off,” so you can skip the usual fuss of transitioning indoor plants to the outdoors. It’s a space-saving, waste-free way to jump-start Vermont’s short growing season.