BELIEVE IT OR NOT, I start my summer garden in December and January, using a neat trick called “Winter-Sowing.” Winter-sowing is an outdoor method of seed germination (invented by Trudi Davidoff) which requires just two things: miniature greenhouses (made from recycled milk jugs) and Mother Nature. You can winter-sow your way to a beautiful garden, too…for pennies. Here’s how:
Make a Greenhouse. You can make a greenhouse from any container you like, so long as light can penetrate its walls. Like other winter-sowers, I use recyclables, including gallon-size milk- or water- jugs, and 2-Litre soda-pop bottles. With jugs and bottles, use a pen-knife to cut around the middle, almost all the way through. The uncut half-inch or so will serve as a hinge.
Next, punch out drainage holes in the bottom. A Phillips screwdriver, heated over a flame at the stove, will facilitate the hole-punching job. Punch out also a few holes along the top portion of the container. These extra holes increase air-ventilation. Ventilation, of course, is the key to preventing excess heat from building up in the greenhouse, and baking the seeds to death. If there is a cap on your jug or bottle, remove it. Watch me make and plant a miniature greenhouse.
Select the Right Soil. It is essential to use a soil mixture that drains well, and has a light, fluffy consistency. A commercial peat-moss and perlite mix is fine. Pour the soil, preferably to a depth of 2 to 3 inches, into the bottom half of your container. Then moisten the soil thoroughly and let it drain.
Sow the Seeds . Sow your seeds on the soil surface, and then cover them with more soil, when necessary, to achieve the proper planting depth. Gently pat the mix down, so that seeds and soil make good contact. Then replace the lid, and secure it with a strip of duct tape, as illustrated.
If you live in a cold climate, as I do, plant your perennial and hardy annual seeds first. Should these sprout during a weird warm-spell in winter, they will not be harmed. Wait until March to plant your tender annuals. More details here: What to Winter-Sow…& When.
Remember to Label! For each sowing, indicate with a permanent marker (or a paint-pen) the seed variety and date sown. Do not omit this step, for there is nothing worse than finding, in spring, dozens of miniature greenhouses brimming with seedlings, and not knowing what they are!
Bring the Greenhouse Outdoors. Your greenhouse, once planted and labeled, is ready to brave the outdoor elements. Select a location that is safe from strong wind, but where sun, rain and snow will be freely admitted. My assorted greenhouses go on the patio table, out of the reach of Lily the Beagle who would otherwise knock them over. For further protection from tipping, I place them in a large plastic box, with drainage holes melted in the bottom.
Relax. Now sit back and let Mother Nature do her thing. As the weather chills and warms, your seeds will freeze and thaw. These natural actions loosen the seed-coatings. This is why advance soaking or nicking of hard-shelled seeds, such as Morning Glories and Sweet Peas, is not necessary when you winter-sow.
At the first kiss of spring, but while nights are still freezing, seedlings will begin to emerge. Now is the time to check for water. Open the tops, and if the soil appears dry, moisten thoroughly but gently, so as not to disturb tender root systems. Then close the tops again. On warm, sunny days, I open the tops for hours at a time, and let the seedlings enjoy the fresh spring air. The tops, of course, are closed at dusk.
I can’t tell you how advantageous winter-sowing can be. Last year I produced an entire garden’s-worth of perennials this way (far too many, in fact), without the need for light-systems, heating devices, or fancy seed-starting kits. And, unlike windowsill-germinated seedlings, which more often than not are frail and spindly, winter-sown seeds grow up to be strong, sturdy plants, completely prepared for glorious careers in the open garden.
If I were you, I’d give winter-sowing a try. Honestly, it’s the easiest, most cost-effective way to achieve a beautiful garden.
Don’t miss a beat at A Garden for the House…sign up for Kevin’s weekly newsletter!
Related Posts:
From Milk-Jug to Greenhouse (detailed instructions)
What to Winter-Sow…& When
Perennials Which Require Cold-Stratification
What’s Sprouting in YOUR Milk-Jugs?
Winter-Sow Your Veggies & Flowering Annuals
Holy cow! What a way to erase the winter blahs! I've never been able to successfully grow seedlings on my windowsills. Lord knows I've tried. But they always got too big too soon, or grew tall and lanky, and then died before it was warm enough here to plant them out. Winter sowing sounds like a plan that I can manage.
When can I plant my tomato seeds? I'm in the same zone as you.
I'll have to try this. After buying poorly grown, half-dead zinnas and snaps (at no discount) from Samascott's last year, I'm determined to grow all of my own summer plants from seed.
When, exactly, should I plant my annuals in mini greenhouses? I'm thinking zinnas, snapdragons, marigolds and the like.
Forgot to say that I'm in zone 5.
Carol – yes, wintersowing is a good way to get an authentic sense of spring! Give it a try!
Eric – wait until late March or early April to start your tomatoes.
Welcome, Tom! Snap dragons are hardy annuals, and very slow to germinate. I would start them the first week in February. As for zinnias and marigolds, winter-sow these in March. They are quick to sprout, and will probably start blooming in their greenhouses in early May. However, wait until Memorial day to give them permanent positions in the garden.
I want to drink all my milk and soda!! I cant wait for spring…..
Erin – winter-sow some delphinium seeds today, and trust me…it WILL feel like spring!
Kevin, where are you finding seeds at this time of the year?
Sharon – you can find seeds at almost any garden center in January. They should be stamped for the current year.
This looks like it might solve a lot of problems. Thank you for the step-by-step instructions.
Also, over Christmas I did put herbs and plants in the kitchen window, including an African violet. You are absolutely right–the plant in the window is differnt from the plant in the room. It brought so much life and warmth to the house. Thank you, again, for all the encouragement.
Neighbors brought me cut flowers last week, 1-2 days after the Christmas decorations were down (and when I was concerned about how to keep the house feeling lovely). Those flowers wilted today, BUT, with the snow on the ground there are green bulb shoots peeking out of the ground. Spring, indeed, is on her way!
Thank you for all the lovely photos which got me through the winter. And also for the tips about planting. It sounds like I should start vegetables and stuff in March winter sowing rather than in the little pots. Nothing grew last year except for the green beans. Maybe this year I will get more…..
Good Morning Kevin,
Wow! I am very excited about this one. I think that even I can handle this and plan to start a couple with kids on Monday. They will make great year end gifts for the teachers.
Have a great day!
Lisa
Janet – Glad you're going to try winter-sowing this season. It really works!
Lisa – Great idea, get the kids involved! And, if I were a teacher, I'd be delighted to receive, in spring, a little “greenhouse” of seedlings. Let us know how your project goes!
MY WINDOW GARDEN IS MAGNIFICENT RIGHT NOW. THE AFRICAN VIOLETS ARE IN FULL BLOOM AND MY ORCHIDS HAVE BUDS READY TO OPEN. I CAN SIT AT MY COMPUTER, GLANCE AS MY BLOOMS, AND SEE SNOW COVERED GROUND OUTSIDE MY WINDOW. HOW DIVINE. I TOO AM ANXIOUS TO BEGIN WINTER SEEDING FOR SUMMER FLOWERS. I REMEMBER YOUR OTHER IDEA AND WOULD SUGGEST TO EVERYONE, KEEP SCENTED CUT FLOWERS ON YOUR BEDROOM NIGHT TABLE FOR THE AROMA AND BEAUTY IT CREATES.
Anne – so glad your window garden brings you great joy. Mine does, too.
If you can, let us know which summer flowers you are going to winter-sow.
Here I go… better late than never. I have pansies, cosmos, geranium pinto salmon and hollyhocks to sew.
Can I use this method with herbs?
Lisa B – Yes, you can definitely winter-sow herbs. I've successfully sown thyme (including the creeping-type), basil and flat-leaved parsley using this method.
Ahhh, this is my favorite part about winter… I can't wait for spring. Do you have a list of plants on what to sow and when? I harvested some seeds from a few plants last year.
Erin – ditto on that “favorite part about winter” thing. Winter-sowing makes me thing it's spring already.
The most important seeds to sow right now are those which require cold stratification.
Holy cow how cool is this!
I can't wait to gather some milk containers and begin.
Queen of the Click – Beware…Winter-sowing is highly addictive!
I planted at least 24 containers last winter, and in the spring, to my delight (or horror) EVERYTHING had sprouted. Everything that is, except the delphiniums (I think the seeds were old).
Dear Kevin, your Winter-Sowing 101 Tutorial is so charming that I cannot resist trying it for the first time on a pack of dwarf sweet peas seeds. I hope that this spring you will add a sequel to it showing the greenhouse graduation ceremony. That is to say, when and how do you plant the seedlings in the garden? How big do they need to be before they are ready to be planted? When do you do that? Best regards, Dana
Dana – What a great suggestion. I did, in fact, photograph the transplanting-process last spring, and then forgot to publish the pictures. I shall correct this soon, lest I forget (again).
What an amazing concept! Can one start most vegetables in this way? Now to find some milk jugs . . . Oh & what if the temperatures fluctuate to -30 and 5 continually?
Anonymous – welcome to A Garden for the House, and also to the wonderful world of winter-sowing!
You can start all of your hardy vegetables now (broccoli, cauliflower, kale, swiss chard, spinach, etc.). For these will tolerate frost after they germinate. Wait until March to winter-sow tender vegetables (tomatoes, peppers, etc.). Otherwise you'll have to cover their milk jugs with a blanket should frost threaten after germination.
Of course any perennial or annual which is hardy in your region (or which reseeds itself) can be winter-sown now. It doesn't matter if temperatures fluctuate. In fact, most of these seeds require such fluctuating temps in order to germinate.
Feel free to ask other questions as they occur to you — I'm here to help! You might enjoy reading my other winter-sowing articles, too.
The quickest way I found to punch the holes is a soldering iron. It very quickly did all my holes so I was ready to plant. Thanks for the great idea.
Terri – soldering iron…excellent. I don't have one, however, so its the red-hot screwdriver for me!
This idea is excellent! Much improved upon over my method. Hope you don't mind, I'm sharing your post with my readers with links back to your site. Find it at http://www.ozarkmountainfamily.blogspot.com. I can't wait to get started!! You have solved my dilemma!!
Sharon – Thanks for the link. I think you will love this method of seed-sowing in the snow. It really works!
WOW!!! Thank you so much for this great bit of information!! I had no idea this was possible. I am the woman who had the spindly plants lining every single kitchen counter, and who spent hours a day transporting those seedlings in and out of the house when trying to get them ready to go into the garden!
Is this equally effective with vegetables like tomatoes as it is flowers?
Thank you so much for this. Found you via Pinterest and will Stumble you now too to spread the good word. Happy gardening!
Tamara – Nice to meet you. Winter-Sowing in milk-jugs works for any seed which will typically reseed itself outdoors. I've used the method for a number of veggies including romaine, spinach, brussels sprouts, peas, broccoli, and yes, even tomatoes. No hurry for the veggies — you can winter-sow them in March. Flowering perennials, however, you can sow in December/January.
The method is not only fun, but it is effective, too. I always end up with more strong, healthy seedlings than I can possibly accommodate!
I've been waiting all year to try your idea. Saving up my milk jugs!
Hope you are having a nice start to the holidays. Somewhere along the way in reading your blog, you said that beautiful china is meant to be used. And so for the first time I bravely pulled out my Haviland china, handed down from a Great-Aunt, and set the Thanksgiving table. It was so lovely. Thanks for all of your super useful info and inspiration.
Fabulous!!!
badger gardener – Well, food tastes better when it is served on Haviland china. This, I believe, is a generally-accepted fact
Genene – Welcome aboard!
Thank you for sharing this wonderful idea, I can not wait to try this
Cathy Reynolds – Welcome. Seed sowing in the snow is highly addictive. But there are worse habits, right?
Wow, I can't wait to try it. I have absolutely no room indoors for sowing seeds… too many cordylines and agapanthas crowding the place. I am assuming zone 5, NH is similar to your climate?
Would this work with veggie plants??
Paula Hunter – Your zone 5 NH location is perfect for winter-sowing (I'm 5-b). Seeds sown outdoors in mini-greenhouses always grow up to be stronger and healthier than those started indoors. Have fun, and let me know what you decide to winter-sow!
a ragamuffin princess – Welcome. Winter-Sowing in milk-jug greenhouses works for any seed which will typically reseed itself outdoors. I've used the method for a number of veggies including romaine, spinach, brussels sprouts, peas, broccoli, and yes, even tomatoes. No hurry for the veggies — here in cold zone 5-b, I winter-sow them in March. Flowering perennials, however, can and should be sown in December/January. You can see my veggie and flowering annual schedule here.
Tried this for the first time last year and got GREAT results. I always send new gardeners your way for winter sowing info, Kevin.
BBI – Thanks! The only downside to winter-sowing is that it's highly addictive.
I tried winter sowing for the first time in February of 2011. I was successful in growing perennial Oriental Poppies in flaming orange, Miniature Platycodon in periwinkle blue, Yellow Baptisia, Great Blue Lobelia, Montauk Daisies, and Candleabra Primroses in dark pink. It took almost no effort and was highly rewarding. All of these were perennial plants. The Lobelia was the most successful, yielding about 50 plants that I carefully upsized twice, finally installing them in my damp shady area on the north side of the house.
Instead of taping the carton’s hinged lid, I threaded a thin piece of bamboo (from my own patch) through the handle hole, into the ground and diagonally anchored the whole shebang against wind. It worked well.
I created holes in the base with an extra long nail and a hammer, sitting the plastic milk carton on the ground with its top open.
I am saving my cartons as we speak to go again this coming winter. I plan to add to the list of perennials, using my own saved seed and some from friends. It’s like a new magic trick!
Beverly – You came up with some terrific hole-punching and container-securing tips. I have to use tape on my miniature greenhouses, because they rest on a table, not on the ground. This because of Lily the Beagle.
One question for you: where did you obtain the seeds of Candleabra Primroses? I have these Primula japonicas in the Woodland Garden, but last year searched for more seeds on-line and couldn’t find them.
All seeds came from my own yard with the exception of my sister-in-law’s Baptisia.
I harvested Primrose seeds from plants which were a catalog purchase about 5 years ago. I think it was Bluestone Perennials, but I am not totally sure. I noticed small seedlings developing near the parents, but they failed to thrive. I wanted more of these plants so I saved the mature seeds and tried them in traditional APS trays first, with no luck (no freeze/thaw to break dormancy). When I tried them in the winter sowing jugs I got 15 very healthy specimens. I expect them to bloom in 2012.
http://www.nargs.org/nargswiki/tiki-index.php?page=Primula+-+Candelabra+types
This link has a photo, first one on the right, which matches the pink ones I grow.
I wanted to start making some money off of my blog, how would I go about doing so? What about google adsense or other programs like it?.
Beverly – I always mean to save some of my ripened primrose seeds in summer. But then I get caught up in other garden chores. This year — assuming the plants return — I’ll try to do what you do: save and winter-sow the seeds.
Do these need to be watered when you first put them in the water jug? I love this idea!
Can you winter plant vegetables?
Laurie – Before you plant the seeds, thoroughly moisten the soil and let it drain.
Shannon – You can plant any veggies you like, with this warning: Should the non-frost-tolerant types sprout too early in spring, you’ll have to cover their jugs with a blanket on frosty nights.
I winter-sow my spinach and other frost-tolerant veggies any time in winter. But I wait until 8 weeks or so before the last spring frost to sow my heat-loving tomatoes, peppers, etc.
Reallllly hate to be a pest, but am planting winter jugs today and am unable to access your ‘winter sowing veggies and annuals’ (sic) link. Have tried to access it many ways, but unable so far. Please help me Kevin and tell me which vegs you’d plant now. I’ve got my flower packets ready, but wonder about vegetables in particular today. Thanks so!
Cary – you are SO not a pest! Here is the link to the annuals/vegetables article. It’s based on my zone 5-b climate (which feels more like zone 7 this winter!).
Although I wait until late March to WS most of my annuals (including veggies), you can, in fact, plant them now. The only drawback to such an early start is this: Should they sprout during a freakish warm spell when it is still very much winter, you’ll have to protect the not-frost-hardy ones. This means throwing a blanket over their containers, or moving them to warmer quarters at night.
If you really want to sow annuals and veggies now, in January, go ahead with frost-tolerant types, including broccoli, cabbage, peas, and lettuces of all kinds, including spinach, kale and swiss chard.
Hope this helps! Keep in mind that winter-sowing is not an exact science…
Oh. You can even sow tomatoes now. They won’t sprout until the soil in their jug reaches 70 degrees or so — which, during normal years, doesn’t occur until May.
Thank you once again! This is exactly what I needed. Thanks too for the reminder that this is not an exact science. I’m trying winter sowing to give me more indoor seedling starting space, while reducing my hardening off tasks later in the season. Hi-ho, hi-ho, off to Spring we go
!
Tomatoes now? You are indeed tempting me…ooooohhhhhhhhhhhh!!!!!!!!!!!!!!!!
Kevin, I read this a few weeks ago and have saved about 8 gallon jugs for my sowing. I live in zone 7 and am wondering if I can start the first week of February?
I enjoy your newsletter and blog very much.
Sharon
Cary – Go for it. Give tomatoes a try!
Sharon Rose – You can certainly winter-sow in February in zone 7. However, if your temperatures are particularly mild then — meaning no below-freezing nights — any seeds which require cold-stratification will likely fail. These types need repeated freeze-thaw episodes in order to germinate.
Hi There,
I am a fairly new gardener. Typically I have always purchased seedlings from a nursery to plant in my garden. This year, I would like to try to grow some annuals from seed in order to save some money. (Also just for the experience of growing from seed.)
I love these milk jug greenhouses. What type of annual flowers would you suggest I try in these? Would petunias work in these? They are my favorite annual. Or are they better started indoors? I have heard that they are challenging to germinate. What about inpatients or saliva?
Drat… I forgot to tell you that I live in zone 5. Sorry.
Welcome, Cathy. Like you, I used to spend untold dollars on nursery-grown annuals. Now I know better.
Impatiens, petunias (one of my favorite annuals, too) and salvia are indeed very easy to winter-sow. In fact, even in zone 5 these plants will reseed themselves in the open garden if the soil is not disturbed in spring. You can sow them now or wait until March.
The list of flowering annuals which can be winter-sown is a long one. I’ve had success with impatiens, petunias, salvia (‘Victoria Blue’ my favorite), plus snapdragons, sweet peas, morning glory, larkspur, bachelor buttons, ageratum, calendula, annual asters and marigolds. All these can be sown in January and February, or later in March.
Wait until late March to sow nasturtiums, zinnias, sunflowers and other heat-lovers.
Let me know what you decide to plant, okay?
this sounds great . i am going to try it.
Janice Foster – Nice to meet you. Winter-sowing is fun but I have to warn you: it is highly addictive!
Kevin, this is my first try with starting seeds outdoors and I’m so excited! Sweet peas, Delphinium, Hollyhocks and Fox Gloves so far (I’m still collecting milk jugs for the next month or so). Thanks so much for this awesome idea! I’ll direct my husband to your e-mail when he wants to complain about jugs in the yard in addition to the light cart in the guest room!
Hallie – Tell your husband to try living here for a week: milk jugs outside, light gardens and window gardens inside. Open a kitchen cabinet, and he will be as likely to find stacked clay pots as canned goods!
Love all of the plants you are winter-sowing; hope you’ll report back on your success!
Hi, Kevin – I just found a link to your site today via Pinterest and I am very interested in trying your project! We are in zone 3b and I wonder if you have any advice about the time to plant here. Thanks so much for your help.
Crystal – Good news for you. Even in zone 3b your winter-sowing schedule will be the same as mine in 5-b. Consequently, plant all of your perennials and hardy annuals while it is still very much winter. Hold off on tender annuals until about 8 weeks before you’d normally transplant to the open garden (meaning late-March or early-April).
And have fun!
Hi Kevin, like many others here, I found you through Pinterest. I would love to start winter sowing asap. What do you suggest I try as a very new gardener. I think I’m in zone 5. Indianapolis,IN
Thanks in advance!
Kim – Nice to meet you. Probably you should follow the same planting-schedule as me.
And have fun…winter-sowing is highly addictive!
Hi Kevin, I tried to post a comment last night, but it wouldn’t go through. Anyway, I live in N. Wisconsin, zone 3, and I’m wondering how far behind your schedule I should follow. We usually have frosts here up until June 5-10. I’m always crazy to get planting before that, so winter sowing would be great for me. Last year, we had a warm spell in March and I put my peas in. They came up a couple of week later and even though it snowed on them a couple of time, they were great. Tomatoes never go in until June 10th and I have had success starting them in my window, but I would love to have everything in jugs outside and not have to haul them in and out to harden off. I’m really excited to have found your website. Thanks for all the info. Shawnee
Welcome, Shawnee. Perennials can be started any time in winter. And right now in cold zone 3 you can winter-sow your hardy annuals (including peas, kale, and spinach).
As a rule of thumb (and it is a rule I often break!), I “winter”-sow my tender annuals (like zinnias) and veggies (like tomatoes) about 8 weeks before I’d normally transplant them to the open garden. For you, this would mean the first week in April. Most of these seeds won’t pop up until the weather warms, but at least you’ll have them planted.
And feel free to experiment with timing. I’ll admit that winter-sowing is not an exact science!
Neat! Very excited to try this! Looks like I have some time to snag extra milk jugs from family and friends before I start my vegetables! We’ve had a ice/snow storm here in Michigan, so I’m gonna give it a couple of weeks before I start mine – sound good Kevin?
Thanks Kevin! I did look on a more detail zone map and I’m actually in zone 4a, but I think it is just easier to count backwards from the dates you know are true to your area. I’m super excited to try this milk jug method, especially because it seems like nature just decides for itself when to sprout and grow. I’m going seed shopping tonight and start planting seeds as I get empty milk jugs. We buy milk in bags from a local dairy, so I’m going to have to switch to store milk or ask around for empty jugs! Thanks for the link to transplanting. I like your analogies to pulling taffee and cutting brownies. I’m reading Eliot Coleman’s 4-season harvest right now and I like what he says about making gardening a year round event (so I don’t go crazy in the winter!)
Hi Kevin. We are in zone 5b and we are getting very warm weather for this time of year. Some 80s and mostly 70s. Will the containers overheat in this weather. They still have not sprouted. Should the tops be opened during this heat spell, I have milk jugs with the cap off and have added extra ventilation holes on top.. Should I also be keeping the soil moist.? Any suggestions will be appreciated
Dave – Bizarre weather, right? Since it has been hot and dry where you are, go ahead and remove tape and open tops on particularly warm days ( 70s and 80s.) Soak the soil, too. Re-close tops at dusk.
Only a few of my winter-sown jugs have sprouted so far. But where I live (Hudson Valley, NY, zone 5-b), mid-March is still early for most seeds.
This may be a dumb question…lol…but when spring arrives what it the best way to move them to the garden?
Laura – Here are the directions for transplanting winter-sown seedlings to the open garden. And…since you are a winter-sower, would you mind clicking on this post so you can tell us what you grew this year?
I am SOOOOO excited to get started with this!!!!
Every year at this time, my south facing windows are crowded with folding tables full of seed trays in an effort to tame a bit more of my Vermont wilderness. White Pine grows like weeds here, and I have everything I can do to keep up with the areas that I have cleared. Now I can get some pretty ground cover started, grow lots of lavender to keep the squirrels and deer away, and get tons more started as well. I’m off to the recycling center to turn my yard into a field of mini greenhouses!!! I WILL take pictures!!!
YIPPEEEE!!!!!
Susie/VT – Go for it!