What to Winter Sow in January

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What to Winter Sow in January: The New England Gardener’s Cure for the “Winter Blahs”

If you are starting to feel the winter blahs and already getting the itch to plant something, I have the perfect fix for you. While the ground in Massachusetts and New Hampshire is currently frozen solid or buried under a foot of snow, your gardening season doesn’t have to wait until May.

January is the “sweet spot” for winter sowing, particularly for those of us in Zones 5 and 6. It’s the time of year when we can harness the power of the freeze-thaw cycle to do the hard work for us. If you’re new to this process, make sure to check out my guide on Winter Sowing for Beginners: The Easy Milk Jug Method to get your containers prepped and ready.

Why January is the Best Time to Winter Sow

In New England, our winters provide a natural process called cold stratification. Many native plants and hardy perennials have a built-in “dormancy” mechanism. They require a specific period of moisture and freezing temperatures to break their seed coats. By sowing in January, you ensure these seeds get the 60 to 90 days of cold they need to wake up when the spring sun finally warms the soil.

Furthermore, winter sowing in January gives you a much-needed mental health boost. There is nothing quite like seeing your “mini-greenhouses” sitting in the snow, knowing that life is already beginning to stir.

Top Seeds to Winter Sow in January

Not all seeds should go out in the snow this early. We save the tomatoes and zinnias for March and April. January is reserved for the “cold-hardy” elites.

1. Native Perennials (The Pollinator Powerhouses)

Native plants are the kings of winter sowing. Since they are adapted to our New Hampshire and Massachusetts climate, they thrive in the outdoor chill.

Milkweed (Asclepias): Essential for Monarch butterflies. Common, Swamp, and Butterfly Weed seeds demand a long freeze to germinate.
New England Aster: A late-season pollinator favorite that germinates reliably in milk jugs.
Joe Pye Weed: These seeds are tiny and love the damp, cold environment of a January jug.

2. Hardy Flowers for Cutting

If you want a lush cutting garden this summer, start these now:

Echinacea (Coneflower): These are sturdy and benefit from a long stratification period.
Rudbeckia (Black-Eyed Susans): Extremely hardy and will often bloom in their first year when winter sown.
Lupine: These iconic New England spikes love the cold and often have better root development when started outdoors in January rather than inside under lights.

3. Culinary Herbs and “Marathon” Veggies

While most veggies wait, a few benefit from an early start:

Lavender: Infamously difficult to start indoors, lavender seeds love the natural stratification of a winter jug.
Onions and Leeks: These are slow growers. Starting them in January gives them the long “runway” they need to produce large bulbs by harvest time.

Pro-Tips for January Sowing in the Northeast

To ensure your January seeds survive the “Polar Vortex” and the “January Thaw,” keep these tips in mind:

Avoid the South Side: Place your jugs where they will stay cold. The south side of your house can get too warm on a sunny January day, causing seeds to sprout prematurely. A north or east-facing spot is safer.
Let the Snow In: Don’t worry if snow covers your jugs! Snow is an incredible insulator and provide consistent moisture as it melts through the open tops of your containers.
Check the Tape: The New England wind can be brutal. Ensure your duct tape is secure so your “greenhouses” don’t fly away during a Nor’easter.

January doesn’t have to be a month of waiting. Grab your seeds, your milk jugs, and a pair of gloves—it’s time to start growing!