Must-Have Seeds to Winter Sow and How to Do It the Easy Way

Are you tired of the winter blues? Are you counting down the days till spring? And starting your garden? Well you don’t have to wait!! Winter sowing flower seeds will give you a jump start on your garden and produce blooms sooner!

There are so many varieties of seeds that are great candidates for winter sowing. Edible cool-season crops, flowering plants, herbs – you have a lot of options to choose from when you’re ready to give this method a try.

Let’s start with perennials. The first quality you should look for when determining if a seed variety is a good winter sowing candidate is the hardiness zone that is appropriate for the perennial plant you’re considering. If it’s naturally hardy in your zone, odds are good that it’s a good option for winter sowing.

There are plenty of hardy annual options too, and the seed packets of those plants will often feature the same key phrases.

What constitutes a “hardy annual?” Those are plants that complete their lifecycle in just one year and which can tolerate a light frost. They germinate, mature, produce, and die within a 12-month period, but they won’t resprout. Instead, they set seed for the following year’s new generation and can sprout in place, without the need to germinate indoors.

Some examples include snapdragon, bee balm, and delphinium; and that’s just the tip of the iceberg. There are so many options to try. Some edible options for winter sowing include the classic cool-season crops – like broccoli, cauliflower and cabbage.

In winter sowing, you need to provide a little protection for you seeds and contain them so that you can transplant them into your garden in the spring. Your goal is to create a mini-greenhouse.

Look around your home, and you’ll find all kinds of winter sowing containers. You are looking for anything clear or slightly opaque to let in sunlight. It also needs to withstand freezing temperatures and if it has a handle, that’s ideal.

Once you have your container you are going to want to drill some holes in the bottom for drainage. You are ready for soil, regular potting soil is perfect. You will need enough soil to allow room for the roots to develop once the seeds have germinated. A soil depth of about 4” is a good rule of thumb.

Sprinkle your seeds over the surface and very lightly tamp them down with your hand.

Water them in gently, then close up the container. Duct tape works great to secure the top and to prevent it from being blown or knocked off.

Let’s dive into winter sowing flower seeds and take a look at the benefits and exactly how you should do it.

Disclosure: Some of the links below are affiliate links, meaning, at no additional cost to you, I will earn a commission if you click through and make a purchase.

What is Winter Sowing

Winter sowing is a method of germinating seeds outdoors in recycled containers during the cold winter months. You don’t need special equipment or a greenhouse. The recycled containers act as mini-greenhouses for you.

This method is great for those that don’t have any extra space indoors to dedicate to seed starting. All you need is some good quality potting soil, containers, and seeds along with the great outdoors!

You can garden inexpensively and this is one method that has been proven to work. If you want you can start with some cheap perennial seeds from the dollar store. Or cheap annual seeds. I have been very successful with a 50 cent pack of seeds so go ahead and give it a whirl!

Why Winter Sow Flower Seeds

Did you know many biennials don’t bloom until the second year? Unless you sow them early!

That is one reason winter sowing is so wonderful plus it is just fun if you love to grow lots of Spring and Summer flowers and have a tight budget.

Not only will you get blooms from the perennials and biennials that take a bit of establishing but you will also have a great big head start on other plants.

Plants grown from seed this way are tougher than those started indoors. Healthier plants equal better success when transplanting!

Also, many seeds need cold stratification to germinate well and they get that cold spell with winter sowing. And to get good flowering many need vernalization.

Vernalization: the cooling of seed during germination in order to accelerate flowering when it is planted.

Stratification: In horticulture, stratification is a process of treating seeds to simulate natural conditions that the seeds must experience before germination can occur. Many seed species have an embryonic dormancy phase, and generally will not sprout until this dormancy is broken

Some seeds with hard coatings also do better with this method as the warming and cooling, even some freezing helps to soften the coat and therefore easier for the seeds to germinate.

Another plus is winter sown seeds don’t need to harden off before transplanting into the garden.

Which Flowers Can you Winter Sow

Not all flowers are a good candidate for Winter Sowing. Generally, it’s best to skip the heat loving plants, like Sunflowers, Zinnias, Celosia, etc. and start those from seed when the weather warms up.

Be sure to look for clues on the seed pack, words like:

“hardy”

“direct sown as soon as the soil can be worked”

“direct sow in early spring”

“chill seeds before sowing”

“can withstand frost”

Perennials You Can Winter Sow

Baptisia
Foxglove
Hollyhock
Columbine
Buddleja
Bachelor Button

Annuals You Can Winter Sow

Snapdragon
Poppy
Yarrow
Sweet William
Sweet Pea

Looking for a printable list of Flower Seeds that you can Winter Sow – CLICK HERE!!

Winter Sowing in Milk Jugs

Start with some recycled 1-gallon milk or water jugs. My sister gave me these, she has 4 boys and they go through a lot of milk.

I wash and sanitize them with a bleach solution. Then using a hot metal skewer or old steak knife I pierce holes in the bottom for drainage.

Using scissors I cut all around leaving a 1 1/2 inch wide band beneath the handle to act as a hinge.

Add a few inches of potting soil to your container, sprinkle on the seeds and press them gently yet firmly into the soil. You need good contact between the seeds and the soil.

Some will say to use a seed starting mix but that is not necessary for this method as winter-sown seeds aren’t as susceptible to damping off and the fungus that plague indoor sprouts. If you are using good quality potting soil you are fine.

Do not use potting soil with additives like water absorbing crystals, synthetic fertilizer (aka Miracle Gro) and things like that.

Duct tape to close up the milk jug and place it outside in an area that is semi-protected so they won’t get blown over by the wind.

I seat mine into the soil of this raised bed to secure them a bit better if we get any strong wind. Pretty soon I will have this all filled with these jugs.

As you can see in the photo you DO NOT want to put the lids back on the jugs. The opening allows water and air to get in.

Maintenance of Winter Sowing Containers

Most of the winter you can just ignore them but after the weather begins to be sunnier you will want to check on them.

Check for condensation on the inside of the containers on any sunny day above 32 degrees F.

If you don’t see condensation you should give them some water by setting the container in water to absorb it through the bottom.

Check for sprouts. They are easily visible down the spout or through the sides of the clear containers. You may be surprised how soon some germinate even when it is still quite cold out.

As temperatures rise you will need to open the tops of the containers or they will overheat and cook your seedlings. Just be sure to close them back up at night.

Once you are opening the containers you will need to stay on top of keeping them watered. With such a shallow amount of soil, they will tend to dry out fast.