Is It Too Late to Try Winter Sowing?

A Simple Guide for New Jersey Gardeners

by Lynn Grillo

Every year around this time, many gardeners ask the same question:

“Is it too late to winter sow?”

The good news is that the answer is usually no.

Winter sowing is a wonderfully forgiving seed-starting method. Instead of fussing with grow lights and trays indoors, you simply plant seeds in recycled containers—often milk jugs—and place them outside. The containers act like little greenhouses, letting sunlight in while protecting the seeds from the worst of winter.

The seeds experience natural cold, moisture, and the freeze-thaw cycles of the season. When the timing is right, they germinate on their own and grow into sturdy seedlings that are already adapted to outdoor conditions. And because different plants prefer different temperatures, the winter sowing window in New Jersey (Zones 7a/7b) actually stretches from January into early spring.

What to Sow and When

January through early February is ideal for hardy perennials and flowers that benefit from winter chill. Garden favorites like coneflower, black-eyed Susan, lupine, foxglove, and Shasta daisy do beautifully with an early start. Hardy annuals such as poppies, pansies, larkspur, and sweet peas can go out now as well.

February into early March is perfect for cool-season vegetables. This is a great time to winter sow kale, spinach, lettuce, broccoli, cabbage, and onions, along with herbs like parsley and cilantro.

By late March, gardeners can start faster-growing flowers and warmer-season crops such as zinnias, marigolds, cosmos, cucumbers, zucchini, and summer squash.

So if winter has slipped by and you are just thinking about starting seeds, you still have plenty of time. Simply choose plants that match the season.

A Simple Winter Project

Part of the charm of winter sowing is how simple it is. A clear plastic milk jug, a few drainage holes, potting soil, and some seeds are enough to get started. Place the containers in a sunny spot outdoors and let nature handle the timing. Weeks later, when spring begins to wake up the garden, those little containers often surprise you with clusters of healthy seedlings ready for planting.

Sometimes the easiest way to start the gardening season is simply to let winter do the work for you.

You can also explore a step-by-step presentation on the technique here (PDF 6.5 MB):