As Calgarians, we know all too well the grip of winter — icy streets, snow-covered landscapes, and the slow wait until spring’s warmth awakens our gardens. With the festive season behind us and the new year in full swing, many of us find ourselves eager to get into the soil. But with the ground frozen solid until April, how can we keep our gardening passion alive during these chilly months?
The Winter Sowing Revolution
Enter winter sowing — a game-changing technique that allows you to start your garden seeds outdoors during the depths of winter. Thanks to the innovative ideas of gardener Trudi Davidoff, this method uses everyday containers like milk jugs to create mini-greenhouses that protect seedlings from harsh conditions, letting nature do the work of germination.
What Is Winter Sowing?
In simple terms, winter sowing involves planting climate-tolerant seeds in sealed containers, then placing them outside in a sheltered spot. These containers act as mini-greenhouses, harnessing the natural freeze-thaw cycles to stimulate germination. Unlike indoor seed starting, which requires special lights and space, winter sowing is affordable, eco-friendly, and perfect for our Calgary climate.
Getting Started in Your Calgary Garden
Here’s how you can begin your own winter sowing adventure:
- Choose your containers: Milk jugs are perfect — sturdy, opaque, and just the right size. But you can also use any container that allows for drainage and ventilation.
- Prepare your jugs: Drill 8-12 drainage holes in the bottom. Cut a four-inch opening in the side or top, leaving the lid attached for easy access.
- Fill with soil: Use high-quality potting soil rich in organic matter. Moisten it before filling your containers.
- Plant your seeds: Sow seeds at the depth recommended on the packet, spacing them to allow for transplanting later.
- Seal and label: Tape the lid shut, label with the plant name and date, then leave a label inside in case the outside gets damaged.
- Place outside: Find a sheltered spot away from direct afternoon sun — under a deck, near shrubs, or on the east or north side of your house are ideal.
A Sample of Great Species for Winter Sowing in Calgary
If you’re ready to give winter sowing a try, here’s a list of excellent plants suited for our Calgary climate, perfect for starting now to enjoy a lush garden in spring and summer:
Vegetables & Herbs
- Beets and Chard (Beta vulgaris, B. vulgaris subsp. cicla)
- Broccoli & Cauliflower (Brassica oleracea var. botrytis)
- Cabbage (Brassica oleracea var. capitata)
- Kale (Brassica oleracea var. acephala)
- Leeks (Allium ampeloprasum var. porrum)
- Onions (Allium cepa)
- Peas (Pisum sativum glaucum)
- Winter & Summer Squash (Cucurbita spp.)
- Herbs:
- Cilantro (Coriandrum sativum)
- Calendula (Calendula officinalis)
- Borage (Borago officinalis)
- Lemon Balm (Melissa officinalis)
- Lemon Verbena (Aloysia triphylla)
- Tomatoes: Big Boy and Purple Majesty varieties
Flowers & Ornamental Grasses
- Nasturtium (Tropaeolum majus)
- Marigold (Tagetes spp.)
- Cosmos (Cosmos bipinnatus)
- Blanket Flower (Gaillardia aristata)
- Coneflower (Rudbeckia hirta)
- Sunflower (Helianthus annuus)
- Sweet Peas (Lathyrus odoratus)
- Zinnia (Zinnia spp.)
- Painted Tongue (Salpiglossis sinuata)
- Morning Glory (Ipomoea spp.)
Annual & Perennial Grasses
- Bunny Tail Grass (Lagurus ovatus)
- Purple Ornamental Millet (Pennisetum glaucum ‘Purple Majesty’)
- Purple Fountain Grass (Pennisetum setaceum ‘Rubrum’)
- Tufted Hair Grass (Deschampsia cespitosa)
- White Pampas Grass (Cortaderia selloana)
Herbaceous Perennials
- Purple Coneflower (Echinacea purpurea)
- Beebalm (Monarda didyma)
- Goldsturm Rudbeckia (Rudbeckia fulgida ‘Goldsturm’)
Invasive Perennials (for experienced gardeners)
- Sweet William (Dianthus caryophyllus)
- Yarrow (Achillea millefolium)
A Few Tips for Success
This list includes hardy plants suited for our Calgary winters, especially those requiring cold stratification or naturally germinating in cooler conditions. Start with these to give your garden a head start in the spring, and enjoy the process of nurturing your plants from seed even when it’s cold outside.
Remember, choosing the right plants depends on your specific microclimate and garden conditions. Whether you’re growing vegetables, herbs, or ornamental flowers, winter sowing can turn our long, snowy months into a season of growth and anticipation.
Happy gardening — and don’t forget to share your winter sowing successes with your Calgary gardening community!
