It sounded so simple! Almost foolproof. It might almost be, but the winter sowing method definitely has some hidden learning curves!
What is Winter Sowing?
You take a gallon jug that’s see through enough to let light through, cut it in half, punch 4 drain holes in the bottom, fill with a pre-moistened seed starting mix, plant your seeds, tape the jug back up with some kind of tape(duct tape works well!) and set your jugs in full sun, somewhere sheltered enough for them not to blow over.
Or in my case, stick them on top of the kids play ground and tie them down so the dog can’t eat em! Whatever floats your boat!
I may also have used hot glue to re-close mine since I didn’t have tape! Works great!
A few months later, voila! Your plants have grown into plants hardy enough to be planted into the ground. All with super low maintenance.
Watering rarely required and no need to bring them inside for the nights.
I watered once a day, unless we received snow or rain, in which case they have been watered free of charge! Yep! No need to worry even when it snows. Pretty legit!
Most people will start their seeds in January with this method. Some choose to let them overwinter. I started mine in February and had great success. Albeit somewhat smaller plants than if I had started in January.
All-in-all a super cheap way to create a greenhouse effect and save space by being able to start seeds outside and not use up precious grow light or window space inside.
What can you Winter Sow?
Perennials or more cold hardy plants. Here is the short list of what I tried this year.
Echinacea aka Purple Coneflower
I found winter sowing to be extremely helpful in keeping surface-sown seeds moist! Not having to moisten a seed tray 3-5 times a day is pretty great! Just sayin…
What Can You Do Better Than Me?
I planted in February. I’ll be planting in January next time to really give them a headstart and be established well by the time I’m ready to plant.
But if it comes down to planting in February or not at all, I’ll choose February every time! The plants won’t be as big, but at least you have plants!
Even though all of my plants came up successfully, some to the point of me having to thin them quite severely. I was pretty sad about the amount of seeds I’d wasted by not being more careful of how I was spacing them.
The picture above is a good example of how much I had to thin my spinach for it to be happier.
Plant your seeds with enough space to be able to break apart root masses without harming your transplants. Milk/Water jugs are pretty small so the amount of plants per container is not fit for a ton of plants.
My spinach had to be thinned like crazy simply because I wasn’t able to keep up with fertilization requirements and they kept wanting to die. Now that I’ve thinned it to 5 spinach plants they are looking so much happier! And growing quicker too.
So if you have a pretty heavy feeder like spinach expect to need to fertilize to keep them happy.
Watering. None needed unless you live in a dry, arid space like we do.
Then water once daily.
Which is still not bad, honestly! Good exercise too if you put them on top of a playhouse! I water my seedlings indoors 2-3 times a day if I don’t have a lid over them. So once a day is really considered a win for me!
I watered them with a hand-held water sprayer through the top. But next year I’ll be trying the soak method. Basically putting them in a pool of water and letting them soak up moisture from the bottom. Thus avoiding watering from overhead and potentially setting back any plants.
Also… You can leave them in there for a LONG time! For impatient people like me, this is hard!
I opened them up to soon. I just cut off a little more off the top of the bottle over the course of a few days. Bad idea in my case, as I fried half my chamomile plants like this. Such a bummer!
I also created a whole ton of extra work as I was now having to harden them off, watch for freezing temps and water even more often.
Leave the bottles closed for as long as you safely can without them getting to hot. I should’ve left mine closed for at least 2 months. 3 months is ideal. I opened them pretty soon after sprouting because, well… Excitement! Does one need a better reason?
Space seedlings inside the jugs well!
Check them daily for moisture requirements. The jugs having dew on the inside is a good indicator that no watering is required. No to little dew=time to water.
Leave the jugs closed until the plants are more established. Plants will most likely be shorter than normal which is fine. This indicates a good healthy and strong plant. But for my next go round, I’ll wait until they have at least a few sets of true leaves before opening them up!
Also beware of scorching the plants! Choosing an overcast day to open the jugs and leave them outside would not be ill advise. Or if overcast days are as few and in-between for you as they can be for us. Harden them off the way you would any other plant!
Most of all. Just do it! Take the first step and try one! Planting something and seeing it grow is so so rewarding! One of the best therapies one can find!
One last thing!
Save all the jugs.. It becomes a slight addiction after seeing the first sprouts come up!
What have you tried winter sowing or what will be your first seed to try?