The Milk Jug Method: How to Start Seeds in the Snow
It’s December. The garden beds are asleep, but your gardening itch is already keeping you up at night. You might be thinking you have to wait months to plant or invest in expensive indoor grow lights.
But what if we told you that you could start your garden right now, outside, using nothing but some dirt and the recycling bin?
Welcome to the magic of Winter Sowing.
What is Winter Sowing?
Winter sowing is a method of starting seeds outdoors during the winter. Instead of coddling seedlings on a windowsill, you create miniature greenhouses using translucent plastic containers—most commonly, gallon milk jugs.
You plant the seeds, stick the jugs outside in the elements, and let nature do the work.
Why This Method Rules
- It mimics nature: Many seeds (especially native wildflowers and perennials) actually need a period of cold and damp conditions (called stratification) to wake up and germinate.
- Hardier plants: Indoor seedlings can be weak and leggy. Winter-sown seedlings sprout when the temperature is right for them. They grow up acclimated to the wind and sun, so you don't have to spend weeks "hardening them off."
- It saves space: No more cluttering your kitchen counter with trays of dirt.
- It’s nearly free: You’re upcycling trash into treasure.
Step-by-Step: The Milk Jug Method
1. Gather Your Supplies
- Clean, translucent 1-gallon milk or water jugs (if you can see your hand through the plastic, light can get through).
- Potting soil (mix without fertilizer is best to start).
- Duct tape.
- Scissors or a serrated knife.
- A permanent marker (or a grease pencil).
- Seeds! (More on what to pick below).
2. Prep the Jug
Throw the cap away! You won't need it. The open spout allows rain and snow to enter and hot air to vent out.
Flip the jug over and poke 4-5 drainage holes in the bottom. This is crucial—without drainage, your seeds will drown in icy water.
3. The Cut
Using your scissors or knife, cut around the middle of the jug, about 4 inches from the bottom. Stop before you cut all the way through. Leave about a 1-inch section near the handle uncut. This acts as a hinge so you can flip the top back like a convertible.
4. Fill and Plant
Fill the bottom half with about 3-4 inches of moist potting soil. Pro Tip: Water the soil before you put it in the jug. It should feel like a wrung-out sponge.
Plant your seeds according to the packet depth. Since these are mini-greenhouses, you can sow a bit heavily and separate them later (this is called the "hunk o' seedlings" method).
5. Label It (The Right Way)
Don't just write on the outside of the jug—the sun will fade the marker by spring, and you'll have "mystery plants." Write on a plant tag or a piece of duct tape and stick it on the inside of the jug, or write on the bottom of the jug.
6. Tape and Place
Flip the top back down. Use duct tape to seal the cut all the way around.
Take your jugs outside. Place them in a spot where they will get sun and rain/snow, but won't get blown over by strong winds. (A milk crate works wonders to hold them upright).
What Can You Winter Sow?
Not every plant loves the cold, but many favourites do. Many gardeners like to start their first jugs on the Winter Solstice (Dec 21st).
- December/January: Sow perennials, cold-hardy annuals, and native wildflowers.
- Bumbleseeds picks: Coneflower, Black-Eyed Susans, Milkweed, Foxglove.
- February/March: Sow cold-hardy vegetables.
- Bumbleseeds picks: Kale, Spinach, Broccoli, Cabbage, Cauliflower.
- March/April (Late Winter): Tender annuals can be done this way, too! Just wait until the hardest freezes are likely over.
- Bumbleseeds picks: Zinnia Elegans, Cosmos, Marigolds.
Then... Wait!
This is the hardest part. The jugs will get covered in snow. They will freeze. This is fine! When the days get longer and the sun warms the air inside the jugs, the seeds will sprout.
The Reveal...
Once you see lots of sprouting, you can remove the top and gently separate the tiny seedlings when they show true leaves (the second set of leaves).
If it’s still chilly outside, simply transplant each one into its own pot or seed starter pod and keep them in your greenhouse.
Harden off plants slowly over a few weeks by bringing them outdoors in the daytime and back into the greenhouse or cold frame in the evening.
Transfer outdoors into pots or the garden and watch them grow!
