Native Seeds of Fortitude: Winter Seed Sowing

If you are planning to add native plants to your garden, Winter Seed Sowing is a great way to do it. Not only is it easy to do, but it also has numerous benefits that make it well worth the effort.

One of the advantages of winter seed sowing is that it allows you to control the growth of the plants while providing the natural outdoor conditions native plants require. The idea behind winter sowing is that you sow the seeds outdoors in containers, during the winter. The miniature greenhouses protect the seeds from animals and harsh weather and allow them to germinate naturally during the spring.

The other benefit? Short of occasionally checking for moisture, you don’t have anything else to do but let nature take its course! Living in a northern climate and having snow -- or so we hope! -- this method also works because the snowmelt adds moisture your seeds need. Lastly, a bonus to winter sowing over traditional methods: plants are accustomed to the outdoor temperatures, and only need a slow introduction to direct sunlight.

Save time!

Winter sowing mimics what nature would do after plant seeds have fallen on the ground in autumn or have been dispersed via the many ways plants have evolved to reproduce. By sowing seeds in the winter, your native perennials can be planted in the spring, taking full advantage of the growing season. Native perennial seedlings may however take a little longer. Some will not be ready to transplant until summer or maybe even fall. I sometime keep mine in containers through the winter and only transplant them the following spring.

Save yourself aggravation!

It is also an excellent way to take advantage of the cooler temperatures and shorter days of winter. Many native plant seeds, being used to our cool winters, require a period of “stratification”. Seed stratification is a process that helps to break the dormancy of seeds, allowing them to germinate more readily. This process is often necessary for seeds that have a hard outer coat, as the coat can prevent water from reaching the embryo inside.

The stratification period varies across plants, from a minimum of 30 days to 3 months; built into the genetic code of the plant is the “knowledge" that it should not germinate until it has gone through a period of cold weather, thereby signaling its biological clock that it is safe for it to begin germination, begin making roots and eventually peek through the soil. Sowing perennial seeds that have not been cold-stratified may leave you watching the soil for signs of life and wondering if your seeds will germinate.

Save Money!

In addition to the benefits and taking advantage of the cooler temperatures, winter seed sowing is also a great way to save money. Buying seedlings or starter plants can be expensive, especially if you have a large garden. By sowing your own seeds in the winter, you can save money by starting your plants from seeds instead of buying them already grown.

Save your containers: recycle and re-use

All you need is:

- Clean plastic salad greens containers or milk jugs in which you will drill holes at the bottom for drainage and at the top to allow rainwater to seep through.

I use 1/8” drill bits, but you can experiment with different tools. One trick I have found to ease the drilling process is to fill your jugs with water and leave them in the freezer overnight, or until it is frozen solid. This prevents your container from collapsing when you push the drill bit against it.

• A good potting soil mix.
• Native perennial wildflower seeds.
• Labels. I like to use paint pens or simply #2 pencil over window-blind slats. Markers’ inks just do not hold out!
• Water.
• Patience: wait, wait, wait… for the miracle!

The Process:

The actual process of winter sowing could not be easier

• Gather your prepared containers.
• Put at least 3” to 4” of soil in each container; wet it well.
• Sprinkle the seeds on the top and if necessary, cover lightly with more soil.
• Label everything.
• Water. Check occasionally to make sure that your mini greenhouses do not run out of moisture.

Place your containers outdoors. Do not place them under an overhang which would prevent rainwater from reaching them. A spot with a good mix of sun and shade will provide the illumination your plants will need come spring, but not so much of it that it would burn the fragile seedlings. I place mine in the northern part of the property.

So, why wait? Start winter seed sowing today and enjoy the numerous benefits it has to offer. Your garden (and wallet) will thank you! For more information, details and examples please visit the Putnam Pollinator Pathway website and view our instructional video.

Photo credit/infographic creation: Robin Hoffmann