Winter Seed Sowing in the Pacific Northwest
I started winter seed sowing three years back and instantly fell in love with this method.
Though not at first.
I saw it mentioned on Pinterest and it sounded so easy. Almost magical. Instead of the “big rush” in Spring, you simply let nature slowly take its course over winter inside a milk jug and then one day- voilà!
The problem was, even after reading everything that I could find on the web, the only photos I saw were of small herds of plastic milk jugs swaddled in duct tape sitting in sunny, snow covered yards, and that is SO not what we have here. Here in the beautiful Northwest our weather tends to be rain on rain, and then more rain and occasional freezes or snow followed followed by a day or two of sun to tease us into not throwing in the towel and then, yeah… more cold windy rain.
In other words, nothing consistent weather-wise.
But I desperately wanted to try it, so I ended up inventing my own method which is kind of the opposite of the milk jug method, and guess what, it works!
Here’s what you need:
Large Clear plastic containers with clear lids
Wood burning tool with point around 1/2” to 1/3” thick
a fan
In a nutshell, this is what I did. I used large(ish) clear containers. I made 2 to 4 rows of venting holes on each side of the containers. I did NOT drill holes in the bottom or on the lid which is the opposite of the milk jug method.
The reason for doing this is because those drips that come from the top tend to rot things in the northwest, and water seeping in from the bottom does the same thing AND invites in all those tiny slugs. Ugh.
At the same time, the holes on the sides invite in air, and air is vital! Having air flowing in and around all those little babies is the secret to raising healthy seedlings in the PNW.
I drilled the holes about 2-3” up from the bottom on each side, again, to keep the little sluggies or other buggies out.
This system has worked beautifully for me.
And now for the details, here’s what I do:
First off, Im all for recycling milkjugs, and recycling in general, but for me personally, I find a sh**ton of milk jugs in the yard on a gray soggy day visually depressing and I already suffer me some super bad S.A.D. in winter. But that’s just me, you do you.
Long story short, this is what I did and it has worked beautifully for me and as a note to those without a greenhouse, this may be your answer!
I bought a bunch of large clear storage containers with clear lids (I found mine at Walmart and after 3+ years they are still going strong). Make sure the lids are clear and that they snap closed securely. I saw some at Costco recently and the price was right, but I’m just not sure they could survive the winds we get here and also, they were just kind of meh. Also, I got them in 2 sizes but a made sure that they were all matching so that I could stack them up and tuck them away come Summer.
Next, after a few futile attempts at punching holes in the sides with a drill (doesn’t work, looks awful, cracks the plastic), I got a woodburning kit. If you don’t have one already, I suggest getting one that has a point that is 1/4”- 1/3” or so in width so that you can make holes large enough. These run around $15 - $24 on Amazon.
This worked beautifully, but the fumes! Just make sure that you do it outside or in a large ventilated space and have a fan going to move those toxic fumes away from you.
And that’s it for the containers
As you can see in the photo, the venting holes let air flow freely around the seedlings. Also note that the containers are sitting on gravel. The ground around them needs to be free of tall weeds which invites little critters in. If you are placing them on a lawn or weedy area, consider putting down some weed cloth.
The lids on the storage containers are plastic and snap onto the top which keeps the wind from blowing them off. In addition, when the weather warms up in the Spring, I simply snap one end of the container and leave the other side resting on top so it lets heat escape.
Pots, Soil and Sowing
I use a variety of containers, depending on what type of seed Im sowing. For example, when Im sowing Sweet Peas, I usually use a 4 inch container. I have found that this generally works for most perennial sesdlings as well as annuals. For perennials and annuals I sow the seeds sparingly. I do this so that each seedling has air flow and more of a chance of succeeding and also because Spring gets busy and sometimes they sit in their pots for way longer than I planned on.
I have used those multi-cell potting flats, just cutting them to fit the bottom of the container, but have found that I prefer the 4 inch pots. If you don’t have enough of the 4” pots, asking around on facebook marketplace is a great place to find all you need.
This year I’m also going to try using tall paper beverage cups (I’ll poke drainage holes in the bottom) for Sweet Peas and Sunflowers or anything that has a long taproot.
For soil, I like to use any good seed starting mix. I personally prefer Premier Pro Mix for sowing seeds indoors or out.
I moisten and mix the soil with warm water. Please note that you do not want the soil soggy. Soggy kills! What you want is soil that holds together in a ball without falling apart.
Once I have sown the seeds (according to directions) I cover it with vermiculite, again, according to the needs of the seed.
For some seeds, I do a quick germination indoors under lights, and then once they pop up, I place them into the tubs and put them outdoors.
Most go straight outside on the east facing direction.
This is important, especially if you work away from home and cannot check on them during the day.
On the East facing side, they get the morning light and then, by noon or so, they are in the shade and out of direct sunlight.
Tips
I start my winter sowing in late Autumn (Sweet Peas etc.) and continue on monthly through early Spring.
I rarely if ever water. There should be enough moisture to get them through the winter. Once it warms up and they start putting on real growth and their first true leaves, if you feel they need moisture, go ahead and water, but bottom water only. That way you can avoid damping off.
And that’s it! I hope this was helpful and please let me know any questions that you may have.
Happy gardening,
Susan
