Winter Sowing – Germinating the Natural Way
When you consider how seeds germinate in nature, it makes sense to sow our own seeds the same way.
In late summer, left to their own devices, seeds fall into the ground. They slowly get covered with leaves and other natural material ready to begin their long winter hibernation in the soil.
As the cold weather sets in and snow covers the ground, the seed toughens up and as spring sets in that little seed will emerge in its own good time, when conditions are perfect for it to start peeking above ground.
July through August (or, in the northern hemisphere, from December through January) is generally a ‘rest time’ for the annual gardener, so if you’re anxious to be ‘out there’ doing something, winter sowing is a perfect way to keep your green fingers active!
What is Winter Sowing?
Winter sowing is the process of setting out our seeds in old plastic containers, and leaving them until they emerge in the spring. The containers act as tiny ‘greenhouses’ protecting the seed from the harsher weather, but allowing enough cold to help them toughen up over the winter months.
When to Winter Sow?
The best time to winter sow is deep enough into winter that a warm spell won’t start to germinate your seeds. The ideal time in the Northern Hemisphere is December through January. I like to begin mine in the week between Christmas and New Year’s Eve.
What to Winter Sow?
You can winter sow annuals and perennials. Make sure they’re seeds that are acclimatized to your local soil type and climate zone. People have had success with everything from tomatoes to berry bushes. I live in Zone 7ish in the N. Georgia Mountains, so this year I’m sowing rosemary, sage, oregano and lavender for my herb spiral garden, golden currents as berry bushes to compliment the wild blackberries, black cumin and early spring greens like Brussels sprouts, cabbage, broccoli and Swiss chard. It makes sense that any seed that volunteers itself easily in your locality is a great candidate for winter sowing.
Winter Sowing Equipment
Transparent or semi transparent plastic bottles – old 2 litre water bottles, milk jugs, juice jugs or any kind of transparent container with a hinged lid are all great winter sowing vehicles. I prefer containers with handles, because it makes them easier to move around, you will choose what’s perfect for you from SLA [Stuff Lying Around].
How to Winter Sow Step-by-Step
Figure 1
- Clean containers — Wash out your jugs and discard the tops. The open top provides an air vent for your seeds.
- Cut containers — If not using containers with hinged lids, stick a serrated knife into the side of the jug, lay it on its side and cut all the way round, leaving about 1.5” [under the handle if using a jug with a handle] so that the top hinges open. (Figure 1.)
- Create air holes — Use a knife or screwdriver to poke holes round the bottom of the container. This is for drainage and is very important. If you don’t make drainage holes, your seeds will drown! If using a container with a hinged lid, poke a few air holes in the top of the lid.
- Add soil — Fill the bottom of the container with about 2” of soil mix. I used regular soil from a garden center, but you can use your own if it’s great soil, and I mixed it with seed potting soil and some cow manure and home made compost. (Figure 2.)
- Water the soil — with a mix of pee and water to give it some valuable nitrogen and leave the containers to drain. (Figure 3.)
- Sow the seeds — on top of the soil, in the same proportion you would if sowing them in flats. I use about 6 seeds in one 2 liter jug and 3 in a small liter bottle, or a few more in a flat hinged container.
- Cover the seeds — with another layer of soil and pat down lightly.
- Seal the container — Seal the cut edges of the bottle or container with light colored duct tape. Leave the top open.
- Label containers — using a laundry marker [better than permanent marker], write on the duct tape what the seed is, the date of sowing and any other info. I like to note where the seeds came from. Or, use a wooden stick that is large enough to write on and pop it into the soil, through the top of the bottle.
Write the info on a label and stick it to the bottom of the container, just to be sure. (Figure 4.) - Set out and leave! — Set out the jugs in a spot that will get the winter sun. Do not leave them on your porch under cover. They want to experience all the weather conditions they would in nature. (Figure 5.)
Figure 2
Figure 3
Figure 4
Figure 5
If you live in a really cold climate, you can wrap a little hay between the jugs to keep them from totally freezing.
Forget about your containers until the spring and you will see them emerge, when they are ready. Most people experience a 75% germination rate, depending of course on the germination rate of the actual seed. If they are low germinators, plant more!
If you are trying this for the first time, it would be wise to start your seeds in the normal way in early spring so that you have backup if for any reason your winter sowing isn’t successful. Chances are once you’ve seen how easy this is, you’ll become a winter sowing devotee.
And then transplant them?
We’ll be winter sowing soon in the piedmont of North Carolina. My first try was last winter with two lobelia varieties- worked really well. I would add that for those who want to be extra cautious, make sure that you remove the top half of your container (no more greenhouse effect) before it gets too hot.
I have to wonder though, wouldn’t the urine fertilizer flush out over the course of winter?
Hmmm, my winter sowing experience has shown me that indelible marker, as used the way it is in the pictures in this article, fades by spring. Write on the bottom of the container where it is not exposed to the weather. Also, add a marker inside with the writing on the bit of the marker that is under the soil. I have markers in the garden that are three and four years old and the writing on the bit below the soil surface is still very clear. Make your markers out of old venetian blind slats or large yoghurt/margarine containers.
Good, basic, concrete information- I’ll have the children get to work on this right away! Thank you for sharing this.
This article is missing the “why winter sow” section. Is there some benefit to this, other than mimicking what happens in nature?
Why winter sow? From our perspective, Nature is random. Sometimes seeds are eaten. Sometimes seeds are washed away or blown away. If you wish to propagate a plant variety from seed and accept Nature’s odds for success, then you don’t winter sow but rather scatter the seeds where you would like them to grow and hope. However, if you want to add to Nature’s odds, you winter sow. After seed germination, many plants need to be potted up to successively larger pots in order to develop the root mass that allows them to survive when planted among well established plants. Winter sowing allows you to do that.
Here in York Western Australia we have to wait for the winter rains that come about the end of April May and some years not until late June then we can plant out direct into the ground and hope we get follow up rains throughout growing season otherwise we have to irrigate our plants and with water restrictions and the cost of water it can be an exspensive exercise At the moment I am toying with the idea of cultivating Aboriginal food plants for use outside of the winter period that can be grown during the late spring/summer period so as not to need town water to grow organic style English/european foods year round
I still don’t get it! Perhaps it is a confusion of terms. I simply call this seed starting, or transplanting, or nurserying. I’m just totally confused about sowing seeds into milk jugs and whatnot in December. I put transplants on a south-facing windowsill in March, never have to pot them up until they are ready to go in the ground. Very little work required. Most garden seeds take 5-10 days to germinate, not months, unless it needs cold stratification.
Jason planting inside requires hardening off. Also plants are more likley to get things such as dampening off, thrips, white flies ect. The idea is put the seeds outdoors the thawing and freezing loosens the seed coats. The plants come up when they are ready many times earlier than if you start indoors. They have stronger root systems and are more frost resistant. If you like starting indoors that’s great! Many of us enjoy winter sowing as a way of getting dirty when it’s way to cold outside. I’m limited in space also so being able to start outdoors gives me the choice to plant more. Hope this helps!
Hi,
This concept was originated by Trudi Davidoff and she has a website called http://www.wintersown.org as well as information at http://www.gardenweb.com in the FAQ section. It was at GardenWeb she first came up with the idea which grew in interest over time. Trudi has registered her notes/method with the USA Library of Congress.
Hey,
Great post I just tried it this year for my first time and did a very brief blog post on it while i worked. I noticed you mentioned “pee” are we talking about the man made stuff good for nitrogen? If so that’s pretty cool! Would like to know more about that? I sometimes loose track of blogs I visit would love to have you stop by and post an answer. I am very curious about the pee? Would help the deer stay away as well as we have a heavy deer population in our area? Thanks for posting and i look forward to hearing from you.
Rodney, PS I am just getting started with humble beginnings.
https://restlesshandswithmanyplans.blogspot.com/
I am curious about keeping the seedlings safe from deer and a hungry groundhog. I have just finished winter sowing hundreds of seeds-vegetables, annuals and perennials (zone 5). To the question, why WS. How could you ever have this many seedlings on your window sill and under the grow lights. The seedlings are hardy and there is no lugging plants outside to harden off. Few opportunities for aphids and disease.
“If you live in a really cold climate, you can wrap a little hay between the jugs to keep them from totally freezing.”
I live in central Europe and get -15°C winters (-20°C if I’m unlucky). Those containers would freeze solid no matter how much insulation I swaddle them in. I have to take in much larger pots just to keep otherwise frost-hardy and locally adapted bushes and bi-annuals from drying out for lack of liquid water.
Also, every time I’ve tried to sow anything before March, in the unheated greenhouse or on the warm window sill, the seedlings shoot up long and then quickly die. Not because of the temperatures, but because of lack of sunlight due to short days, low sunlight angles and interminable cloud cover. I just killed another batch of special short-day, -10°C frost-resistant mustard greens, because apparently November/December is just too short on sunlight even if temperatures are still mostly above freezing. So there is more to consider than just how low your winter temperatures drop. Just because the Gulf stream mostly spares me Canadian winters, doesn’t change the fact that I’m still on the same lattitude as Calgary. I suspect people living around London would have similar problems, even if their winters are warmer than mine. And what use is it for mediterranean herb seedlings to get an extra-early start outside when that’ll just mean they’ll be killed by the Ice Saints in May, 4-6 weeks after they ‘think’ the winter is over? Don’t try to generalise from your limited local experiences, is all I’m saying.
Of course, there are seeds and bulbs that actually need the frost to germinate. But those go into the ground in October here, November at the latest, not when the ground is likely to already be frozen. Again, don’t generalise for the entire northern hemisphere from the United States coasts’ balmy climate.
(Also: December and January are low maintenance? I want to see the gardener that’s finished with all the leaf clean-up, perennial back-cutting, frost-protection measures and leftover repairs before Christmas. January is only off-time if there’s snow and ice on the ground, but not enough to require daily showeling and sanding. Otherwise, it’s the ideal time to fix bird nisting houses, bee hotels, and for cutting dead branches or to start the fruit tree pruning, if the nights aren’t too frosty. There’s never enough time for that later on, and you have to be finished before the frost ends and the sap rises. I also plan to be finished with a couple of new raised beds before I need to start sowing the long season vegetables in March. Didn’t have time for that before the harvest and perennial-planting season was over.)
Wondering what temperature to set when using a frame containing a soil-heating cable
Wanted to respond to a couple of things. First that Trudi didn’t “start” winter sowing – people have been winter sowing one way or another since we’ve had glass (think cold frames). What she did was a great job of marketing the use of waste plastic for the purpose.
The other is “why winter sow.” When you winter sow, you get seedlings that are much more robust and already acclimated than those you can grow indoors. It’s comparatively effortless – no lights, no constant watering (they rarely need watering at all), no feeding (I add compost on top – no feeding necessary), no fussy temperatures, no stratification and none of the loss that I experience in the ground. For me, it’s a winner.
Please comment about the best time to transplant. Last year was my first year. I started echinacea seeds around the New Year in a suburb of Atlanta (zone 7b). Germination was great. However none of the plants made it to maturity. I may have over seeded and based on the volume of sprouts I wanted to get them in the ground before the roots became too tangled. I’m trying again this year but I’m limiting the amount of seeds per container. Assuming over seeding was the main issue, when is the correct time to transplant – after a certain number of true leaves, after the seedlings are approximately X inches high, or some other benchmark? Someone mentioned transitioning seedlings from winter sowing containers to pots before putting them in the ground. Please discuss this in more detail. Thanks!