I'm new to winter sowing this year, but I did sow Virginia Bluebells/Mertensia virginica in December in milk jugs and it was one of the first of my seeds to sprout. The sprouts are looking very healthy now, and I think they will be ready to plant out soon. I got the seeds from Prairie Moon. Don't know about any of the others...mostly doing meadow-type natives instead of woodland ones this year, except for the bluebells.

The problem you will find with most of the plants you mention is they will either have short-viable seeds, or the seeds will establish double dormancy if allowed to dry so they are best sown very fresh. You can use the winter sowing method, but should sow right when seeds would ripen on the plant in your area....many of those you mention when left outdoors will then germinate the following Spring.

Example, I've sown trillium seeds and had them germinate in Spring, but sown the same day they are collected - mid-July here.

Jeffersonia, Thalictrum thalictroides (aka anemonella thalictroides) germinate reliably, but only when sown freshly harvested. To do that, you need to find a trader who will send you fresh seeds, find a seed company who sends seeds moist packed, or what I often find easiest - buy one plant, harvest the seeds when ripe and go from there.

This is my first year wintersowing, and I'm trying virginia bluebells and shooting star. The seeds were from Prairie Moon. No sprouts yet on the shooting star, the bluebells jug has two sprouts that are getting their first true leaves right now.

I have a shady area next to my garage and I am planning on trying some trillium, trout lily, and dutchmans breeches there eventually as well.

I too ordered Mertensia virginica seeds from Prairie Moon nursery and have 1 sprout so far. I hope to have more! Have sown some other woodland flowers, but not the ones you listed. I received some Dicentra canadensis (squirrel corn) seeds from a local GWer last summer, sown right away in a little pot, and those are sprouting now.

Yes, I have done many woodland wildflowers and am expecting to specialize in growing them as a nursery when im out of school.
Its so fun too because I sowed them all in spring/summer of 2008 and they are all just now sprouting!!! It took them 2 years just to sprout! but they are coming up in huge numbers. Heres what I currently have sprouting:
Dutchman's Breeches and Squirrel Corn (LOTS)
Mayapple (LOTS)
Dolls eye/ Baneberry (LOTS)
Forest Phlox
Trout Lilies
And im sure many more to come.
The mayapples are so cool! little tiny umbrellas!
Most of these seeds need to never dry out and be subjected to a warm/cold/warm period or even longer. SO DONT THROW OUT YOUR FLATS IF NONE SPROUT THE FIRST YEAR OR TWO! and you need to keep them moist.
Good luck!

I am happy to hear that Dicentra cucullaria and Mertensia virginica can be easily grown from seeds.
I hope they self sow. :-) Love those plants.
For the past 3 years I have added Mertensia virginica to my garden.
I have been counting the sprouts. :-P I got at least 100 shoots now.

As to Dicentra cucullaria, I just received 5 plants from Edelweiss Perennials.
All very healthy looking.
I am waiting for the rain to stop. I might go get some grits to mix with my soil before planting these precious little things. :-)
I will have to watch out for blooms. They may or may not bloom this year. Who knows. :-)

Definitly good to know about the mertensia! I know where a patch is growing and hopefully i can gather seeds.

I do really want to find a source for jeffersonia seeds, but since they take like 4-5 years to flower (from seed), and it must be sown fresh... maybe it will have to wait till i have a permanant home to put them in.

hopefully i can gather someone trillium seeds as well, if i can time it right :)

Pitimpinai- i want to see pictures of your Mertensia!

Dodecatheon meadia is easy from seed via WSing and the seeds stay viable for a long time. I had a bumper crop in 2006 and have been growing a container from that batch every year, just to see how long they will stay viable. I haven't had any germination yet this year (nothing from the shady section has yet) but they were just fine last year. The problem with these is how long they take to bloom from seed, I'm still waiting on even the oldest seedlings to show me something. The Dodecatheon pulchella I sowed in 2004 started blooming 2 years ago. So be prepared to be patient.

Here's a photo I took today of the Virginia Bluebells/Mertensia virginica seedlings I winter-sowed. Going to plant them out soon.

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The Virginia bluebells are all in bloom here in PA, so I also snapped a couple of pics today of some growing wild on the land we live on. These are posted below. I hope someday my little seedlings look like these!

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