For many gardeners, winter is a time to rest and take stock after a busy growing season.
But for those with the greenest of thumbs, there is no such thing as a gardening off-season! Winter seed sowing can be a great way to get ahead for the next growing season, as well as add some winter diversity to your garden.
Here are our top tips for successfully sowing seeds in winter.
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What is Winter Sowing?
Winter sowing is a seed-sowing method that allows you to sow your seeds in containers outdoors in late winter or early spring.
The containers are then exposed to the elements—snow, rain, heat, and cold—which helps to stratify the seeds and breaks down their hard coatings so that they can germinate more easily.
Once the seeds have sprouted, they are moved to a protected location until they are ready to be transplanted into your garden.
Winter sowing is especially helpful if you are growing seeds that need to be scarified or stratified.
These seeds need some kind of trigger to break dormancy and create germination – just like what happens in nature, where some seeds fall to the ground and need to survive the winter before they sprout, it’s the same with winter sowing.
Examples of seeds that require this scarification (or at least perform better after scarification) include milkweed, nasturtium, beans, and okra.
Other varieties of seeds that do well with winter sowing are those that are described as “pre-chill”, “cold-hardy”, “self-sowing”, or “sown when cool”.
Why Sow Seeds in the Winter?
There are several reasons why gardeners love winter sowing. First of all, it’s a great way to get a jump start on the gardening season.
With winter sowing, you can sow your seeds six to eight weeks before the last frost date in your area, which means that you’ll be able to transplant your seedlings into the garden sooner than if you had waited to sow them indoors.
One of the best things about winter sowing is that you don’t need to buy any special equipment or grow lights. You can sow your seeds in any old container, and there’s no need to sterilize the seedling pots or trays.
In addition, winter sowing is much less work than starting seeds indoors because there is no need to maintain and monitor things like artificial lights or heating mats.
And since the containers are outdoors, you won’t have to worry about watering the seeds as often.
There’s also no risk of the seedlings damping off because they are growing in their natural environment.
Winter-sown seedlings don’t need to be hardened off either, so you can start planting them much earlier in the season.
And because they are already accustomed to the colder temperatures, they are hardier and more robust, which means they have a much higher survival rate.
Lastly, winter sowing is a great way to recycle plastic containers that would otherwise end up in landfills.
Which Seeds Can You Sow in the Winter?
Just because the temperature outside is chilly doesn’t mean you can’t get a jump start on your gardening for the spring. In fact, winter is the perfect time to sow many different types of seeds. Not sure which ones?
One type of seed that can be sown in the winter is brussels sprout seeds. Brussels sprouts are a cool weather crop, which means they grow best in temperatures between 60 and 65 degrees Fahrenheit.
If you sow your seeds in late winter or early spring, you can expect to see seedlings emerge in about four to six weeks.
Another type of seed that does well when sown in the winter is sweet pea seeds. Sweet peas are a type of climbing plant with fragrant flowers that come in a variety of colors.
They prefer cooler weather and do best when sown in late winter or early spring. You can expect to see seedlings emerge in about four to six weeks.
Lettuce seeds are another good option for winter sowing. Lettuce is a cool weather crop that grows best in temperatures between 60 and 70 degrees Fahrenheit (15 to 21 Celsius).
If you sow your lettuce seeds in late winter or early spring, you can expect to see seedlings emerge in about two to three weeks.
Though it may seem counterintuitive, winter is actually an ideal time to sow many types of seeds.
In fact, cool weather crops such as the ones listed above as well as spinach, kale, and carrots actually prefer cooler temperatures and will germinate more quickly in the winter months.
When to Sow Seeds in the Winter
With careful planning, it is possible to have a beautiful garden year-round. One of the key advantages of winter seed sowing is that it can help to extend the growing season.
By starting seeds indoors in the winter months, gardeners can get a jump start on the spring planting season.
You can start your seeds at any time throughout the winter, but keep in mind your local temperatures, as well as the type of crop you’re growing. You’ll want to make sure your seedlings have just enough warmth to germinate and grow well.
Winter Seed Sowing: Step-by-Step Guide
Sowing seeds in winter may not be something you have considered before, but it is a great way to get a head start on your gardening! By following these simple steps, you can sow your seeds now and have them ready to transplant come spring.
1. Start With Clean Equipment
Make sure that all of your pots, trays, and tools are clean and disinfected before you start sowing your seeds. This will help prevent the spread of disease and ensure that your plants get off to a healthy start.
2. Choose the Right Container
The first step is to choose the right container for your winter sowing. You will need something that is clear and can be sealed shut.
Jars, recycled plastic containers, and even take-out containers work well. Just make sure they are clean and dry before you begin.
3. Prepare Your “Mini-Greenhouses” Ahead of Time
If you are using recycled containers, you will need to punch holes in the bottom for drainage. If you are using jars, you will need to screw on the lids snugly, but not too tight.
You will also want to label each container with the type of seed you are planting as well as the date.
4. Add Soil
Fill each container with a potting mix, leaving an inch or so at the top. You can add a handful of sand or perlite if you like, but this is not necessary.
5. Plant the Seeds
Once you’ve prepared your soil, it’s time to actually sow your seeds. Be sure to plant them at the correct depth and keep them evenly spaced so that they have enough room to grow once they come up.
Old seed may not germinate at all, so it’s important to use seed that is as fresh as possible. You should also make sure to buy seed from a reputable source—cheap seed may be lower quality and may not germinate as well.
6. Label Carefully
Once all of your seeds are planted, it is time to label them. This step is important because it will help you keep track of which seeds have germinated and which have not.
You can use stakes or popsicle sticks for this step- just write the name of the seed on one side and the date on the other. Stick the labels into the soil next to each plant.
7. Put Lids On
Now it is time to put the lids on your containers and seal them shut. If you are using jars, screw on the lids snugly but not too tightly. If you are using recycled containers, seal them with duct tape or another type of strong tape.
8. Move Your Winter Sown Containers Outside
Find a spot outside that is protected from wind and animals but still gets some sun during the day. A south-facing porch or windowsill usually works well.
Once you have found a good spot, arrange your containers so that they can get some sun during the day but are still protected from harsh winds and temperatures at night.
9. Leave Them Until Spring
You can leave your winter sown containers outside until it is time to transplant them into your garden in springtime. The plants will sprout when they are ready, so there is no need to check on them every day.
Just make sure they have enough water- once or twice a week should suffice unless there has been a prolonged period of drought conditions in your area.
10. Consider Venting in Hot Weather
Place the containers in a warm, bright spot, and make sure to ventilate them if it gets too hot. Most seeds will need a temperature of about 70 degrees Fahrenheit to germinate properly.
11. Remove Lids When Seedlings Touch the Top of the Inside of the Container
Keep an eye on your seeds and make sure to remove any lids once the seedlings start touching the top of the inside of the container. Water them daily at this point.
12. Cover for Freezing Temperatures
In late winter and early spring, overnight frosts can still occur. Be sure to protect delicate seedlings from frost by covering them with the original cover, a frost blanket, or plastic sheeting if frost is forecasted.
13. Transplant into the Garden
When transplanting into the garden, make sure to harden off your seedlings first.
This means slowly acclimating them to being outside by putting them in a shady spot for an hour or two each day and gradually increasing the amount of time they spend outdoors.
After about a week of hardening off, they should be ready for transplanting into their permanent home in your garden!
How Long Do Winter Sown Seeds Take to Grow?
I am often asked how long it takes winter-sown seeds to grow. The answer, of course, is that it depends on the type of seed. Some seeds will germinate quickly, while others may take weeks or even months.
Different types of seeds have different germination times. Some common winter-sown seeds and their respective germination times are listed below:
- Beets – 21 days
- Broccoli – 21 days
- Cabbage – 21 days
- Carrots – 28 days
- Lettuce – 7-10 days
- Onions – 28 days
- Peas – 21 days
- Spinach – 7-10 days
- Squash – 10-14 days
As you can see, there is quite a range in terms of seed germination time.
How Late Can You Winter Sow Seeds?
The first thing to consider is what kind of plants you’re trying to grow.
Some plants, like hardy annuals, can be sown quite late in the season and still do well. Others, like tender annuals, need a bit more time to mature and should be sown a bit earlier.
If you’re unsure whether a particular plant falls into the hardy or tender category, a quick internet search should give you the answer.
Another thing to consider is your climate zone. In general, the further north you live, the earlier you’ll want to start your winter sowings.
This is because spring comes later to northern climates, so your plants will need all the time they can get to mature before the frost comes again in fall.
Conversely, if you live in a southern climate where spring comes early, you can afford to start your seedlings a bit later.
Finally, it’s important to remember that winter sowing is meant to take advantage of cooler temperatures and shorter days.
So even if it’s technically still winter according to the calendar, if spring-like conditions have arrived in your area, it’s probably too late to start your winter sowings.
Once daytime temperatures consistently stay above 50 degrees Fahrenheit and night-time temperatures are consistently above freezing, any seedlings you sow are likely to experience stress and may not do well.
Does Winter Sowing Really Work?
Winter may be a time for rest for some gardeners, but for those with a green thumb, there is no such thing as an off-season!
Winter seed sowing can be a great way to get ahead for the next growing season, as well as add some winter color to your home.
Just remember to start with clean equipment, use fresh high-quality seed from a reputable source, provide adequate light and warmth, keep an eye on moisture levels, and be patient!
With these tips in mind, you’re sure to have success when sowing seeds this winter!
Rebekah is a full-time homesteader. On her 22 acres, she raises chickens, sheep, and bees, not to mention she grows a wide variety of veggies. She has a huge greenhouse and does lots of DIY projects with her husband in her ever-growing homesteading endeavor. Learn more about Rebekah here.