Hi!

I'm asking this question here because it's more a general knowledge ? about sowing seeds in the winter, not necessarily in containers. I'm trying to understand how this works.....some people cold stratify in the fridge (not freezer or freezing temps), some people winter sow leaving containers outside but they don't live in a cold enough place for ground to freeze and essentially bind any moisture up in crystals...sucking it out of potting medium...so their soil is perpetually damp and moisture surrounds seeds, then some people, such as myself, live in areas where the ground is frozen solid for a few months over winter (water is bound up in crystals and not exactly surrounding the seeds) and I'm wondering how these 3 methods can be and are successful since there is a great range of conditions. What is the difference between putting seeds in freezer in soil and putting them in containers that freeze over the winter? What is the difference between leaving packets (storing dry) in fridge and putting them in a place where water crystallizes out of soil for most of the stratification period?

My other question is...how important is it to fuss over whether ones soil medium is damp enough for germination? I have a choice: put out seed containers in area that small critters frequent and I can't protect but that has contact with ground and receives more ambient moisture or put the containers on an elevated deck where they would receive intermittent snow fall but the soil would be frozen or fairly dry most of the time and I am gone for most of the winter so am not able add water to the pots?

For germination , the seeds must imbibe water into themselves.
When I winter sow, I usually leave the seeds in the moist medium
for over night or several days before I put them outside.
There is much information in the Wintersowing forum here, and on the original Wintersowing site : Wintersown.org

I use the "milk jug" method of wintersowing. This protects the jugs a bit from critters, because you wire back on the top half of the cut-up jug, but you leave the cap off so a little rain/snow will get in so it stays wet enough. Then you just put them out in the yard, or on the deck, but it does need to be where the snow falls on them. Also many (not all) seeds like some light, this is another trigger for sprouting, and they seem to get enough light in the jugs. Mother nature does the rest! This is mostly for perennial plants and shrubs, tree seeds, although some annuals do fine too . Tender more tropical seeds and many garden vegetables it is pointless, they want warmth and sprout fast so just sow them in spring.

If you did winter sowing after your yard is frozen solid, probably you should do like Caroline from the frozen north, and leave them warm and moist a few days before putting them outside. Or do it before it freezes, like now. For me in chilly rainy Seattle, I need to get it done in December so they will get enough cold weather, generally here it is above freezing so they have plenty of moistness without being frozen. Some seeds take two years to sprout! These I move under a cedar tree so they don't get too hot in the sun.

Yes you can stratify in a moist medium in the fridge ( vermiculite or perlite or potting soil or just a moist paper towel), and this often works, or some people put the seeds in similar moist medium, seal them in a big plastic bin, and put them outside to be cold. The fridge can be a great choice, with baggies you can stratify lots in a very small space. Some people have experimented with briefly freezing stubborn seeds, they say it can help but I have never tried it.

Long term cold storage of dry seeds can be done in the fridge or even a deep freeze. When they are dry they do not sprout, but go into a sort of hibernation. But the small frost free freezer in your kitchen refrigerator is not a great choice because it will cycle up around freezing a lot.

You are asking all the right questions!

Thank-you both for your suggestions. I have actually sown using milk jugs before and last yr I went a step further, I cut the bottoms off the milk jugs and sunk them in holes where I wanted the plants to grow permanently and then I pulled the milk jugs out when the seedlings were ready...sort of like a cloche. Problem is I live in a "wild" area. It is wooded and full of raccoons, bears, mice, moles, woodchucks etc etc and over the winter the mice (or something else) found many of my seeds. Raccoons are extremely handy at handling milk jugs and so really the only safe place for my milk jugs is the elevated back deck as there is no easy tree access for curious raccoons. I am usually gone for a couple of months in winter and with the drought we are having I guess I'm wondering if there will be enough snow to keep the jugs moist but maybe this doesn't matter if I, as you both said I should, soak before sowing.

One other ?...if I were to put my seeds in vermiculite and bag them and leave the bags outside, I assume that with the outside being colder than a conventional fridge that even if I were to leave them longer than the suggested stratification time they would not germinate until the outdoor temps rise in the Spring? Thanks for your help!

With all your animal problems, I would start indoors. Cold moist stratify in the fridge for 1 - 2 months. Start seeds in March in seed starting media - preferably on heat mats and under lights. No animal problems.

Another outdoor option but still subject to some problems from animals. Plant seeds in small pots. Sink the pots in a protected area all the way to the brim. Place wire mesh - even screen wire over them. Water. Cover with leaves. If you did this near the foundation, that would add some protection. The finer the mesh - i.e. screen - the sooner you will have to remove it.

WRT some of the original questions. You will do best when you can mimic nature as much as possible. Regardless of what or how done, temperate zone perennial seed must have cold moist stratification.

I have to agree with David that if you have animal problems it would be best to just do it inside. I live in frost free California and I still have to start perennials inside due to animal problems, the little devils just seem to always find my seeds and seedlings! I also do a lot pots in the greenhouse, other than a lone snail I don't get any critters in there.

Aha! Now I have a bunch more ?s regarding "greenhouses" but first, thank-you David for your sound advice! Indoors is prob the answer. Last yr I wanted to populate a small area w/paw paw trees. We actually are overrun w/paw paw trees...they're native and unpalatable to deer....so I thought to fill an area w/the these trees to protect some of my other seedlings in a few yrs. I sunk pots all over, applied window screen, weighed screen down w/rocks....pinning it down w/stakes is impossible around here because the ground is largely rock....and lo and behold...all 16 of these pots were wrenched out of the ground and the contents strewn far and wide....not a single paw paw seed was recovered. I'm guessing bear...it happened in Spring as temps were rising..*sigh*.

So inside is a better bet for me. Problem is I don't have space or $ for proper equipment BUT we do have a little "hut" that the kids play in and I was thinking of growing things in there...but my reservation is that it is maybe not mimicking natural conditions...i.e. heavy snowfall/moisture and temp fluctuations since it retains heat more effectively than outdoors though it is not artificially heated. (All of the species are native to Mid-Atlantic region so they require some degree of stratification). Let's say I soak seeds well before stratifying, I put them in ziplocks or pots in ziplocks and seal them for the couple of months I am gone (not able to water them) would this work? Dee, when you start plants in a greenhouse do you let them germinate as they would outside or do you control temp and go for early germination?

Placing seeds in plastic bags or containers with moist vermiculite is a good way of winter sowing. Several of us have done that, and it works too. My problem was that it was too easy to start too many seeds.
In milk jugs or pots of soil-I can leave them until I get around to transplanting.

Caroline, You are wise :)! I always have too many seeds....and as with so many other sow-from- seed-aholics I repeat that same mistake year after year! For me, though, sadly most of my seedlings don't survive. I don't have a garden or area that I can protect....sort of by choice....I live in a woodland and am surrounded by neighbours who choose to have gardens of grass...they don't plant anything because the deer are too high in number....I prefer to encourage the woods to regrow so my patch looks like a overgrown wasteland (at least the critters have a home!) at the moment....hoping one day that it might rejoin the rest of the woods...in the meantime about 90% of my seedlings are lost....so I don't have a problem with transplanting...I just find a shady spot surround it w/logs and plant, repeat etc. Fool marching to the brink !

Helping nature is good!
I do some of that too!
I just have a large city lot, but the trees and shrubs are taking over.
Squirrels, hares, magpies and birds to contend with.

I'm new to winter sowing and live in zone 5b. I placed my first winter sown jugs outside in January but now in February I'm noticing that the dirt inside the jugs is frozen completely and hard as a rock, is this normal??

Probably so! Where do you live? I assume you're having freezing weather, so, yes, your jugs will be frozen, so to speak! When spring arrives, look for little green guys in there.

So, where do you live?

Karen