Winter Sowing

Winter sowing is a simple way to start seeds outdoors using everyday containers as temporary shelters. Seeds rest through winter and sprout when conditions are right—guided by temperature, moisture, and seasonal change, without the need for schedules, indoor space, or equipment. Milk jugs, greens containers, bakery clamshells, and more become simple "mini greenhouses."

This method works especially well for native plants and cold hardy annuals adapted to winter conditions. It mirrors how many plants naturally germinate in the landscape.

• January–February: Ideal for native perennials and other hardy plants.
• March: Works well for many annuals and warm-season growers.

In mild winters, seeds may sprout earlier. In cooler or variable weather, they may wait longer. Both are normal. Winter sowing gives seedlings a seasonal headstart on growth.

• Use a clear container (milk jug, bottle).
• Poke drainage holes in the bottom.
• Cut the jug almost in half, leaving the handle attached.
• Add 3–4 inches of potting mix.
• Sow seeds according to packet depth.
• Water gently and tape closed.

Remove the cap and place outdoors, exposed to weather. Snow and rain are fine.

• Check occasionally to be sure soil hasn’t dried completely.
• Look for condensation as a sign of moisture.
• Open containers on warm days for airflow.

Some seeds sprout early. Others wait weeks—or longer.

Not every seed will sprout. Not every container will look the same. This doesn’t mean the activity failed.

There is no wrong outcome—only different things to notice.

As temperatures warm, open containers more often and allow seedlings to adjust gradually. Transplant once plants have true leaves and stable weather.