6,340 Garden Web Discussions | Growing from Seed
If you have the woody sub-shrubby type, stratifying isn't necessary -
Caryopteris bungei, and incana , Sow on the surface at 68ºF in light, germinates in less than two weeks - short viable seed (Clothiers)
I haven't grown c. divaricata, but 6 - 8 weeks moist cold seems like the way to go with those. This time of year, prepare your seed pot, write the date on it, wrap in Saran, and put it in your refrigerator.
Here is a link that might be useful: 
If you have dried cleaned seed -
Arisaema triphyllum , Sow at Max. 41ºF, germination irregular, often several months
If you have fresh, or seed not yet harvested, you might read through this article by Tony Avent
Here is a link that might be useful: Tony on the Road - Arisaema
Most of the ~ "seed collecting" site:.edu ~ hits or related to the collection of "native" seed, presumably in the wild. Is this your area of interest? The link below references a book on collecting vegetable and ornamental seed.
Here is a link that might be useful: missouri.edu site
Try the FAQ in the link below.
Here is a link that might be useful: Spring and Summer Sowing (with seed lists)
Many perennials seem to do better at surviving winter if they've reached a good size before frost. If you do sow seeds for fall germination, I would mulch them thickly as soon as the ground freezes solid and pare back the mulch gradually in spring.
I started mine under lights about 1.5 months ago, they are outside in hte garden in my flower box already! Mine had NO prob. germinating with just reg. planting soil!! I put them in 1 gallon milk plastic jug cut in 1/2 and they all came up! I used Morgan and Thompson seeds! They are now like......8 leaves and the leaves are like 5-6" each.
I dumped a big bag of manure in my front flower bed, Didn't mix it in, just spread it evenly over the top. Kept it nice and moist for a couple weeks. My neighbors cat didn't like it and found a new place to go. Then just before I was ready to plant in the bed I mixed it in real good.
Pam
There's the Winter Sowing Exchange and Growing from Seed forum. Also Hudson Seeds and Thompson Morgan have good help sections. For germination and seed identification I go to:
tomclothier.hort.net/
http://theseedsite.co.uk/seedpods.html
http://www.virtualseeds.com/Germination.html
There are members that are much better informed than I. The members at the winter sowing exchange are very into growing from seed.
Barbie