Well you dont want to collect from St. John's Wort...as a matter of fact you should be making sure with your weed board that these are not noxious in your neck of the woods. I don't know where you are, but these are noxious weeds in a few states...I know California, Colorado, Oregon, Idaho, Montana, Nevada, South Dakota and Washington are 8 of those states. They have released a certain beetle (brought from Europe) in ID and WA to fight it and possibly in other places by now. I collect seeds from Wild Bergamot (M. fistulosa) in October...seeds take a long time to completely mature. Mine are due to bloom in the nest week or so and are in bud now. I don't know about the rest....my Liatris failed to germinate for me (sniff sniff) this year.

Vera

Almost all seeds are dry, sort of hard, and black or brown when ripe. The pods or flower heads that grow the seeds will turn dry brown or straw-colored, and typically the seeds will be ready to fall out, shake out, float away, etc. This can take a long time - for example I collected butterflyweed seeds last november that were just getting ready to fly.

By the way, the wild bergamot is very easy to transplant without really impacting the original plant. At the base of each plant will be small "rummers" (stolons, if you're a botanists) that form new stems in an expanding clump. You can separate a few stems and a couple of stolons (and some soil underneath - use a sharp shovel) from an established clump and transplant. Replace a little soil in the hole you left behind and the original plant will create new growth to replace what you have taken. By transplanting this summer you can have blooming plants nest year. Others such as butterflyweed and blazing start probably won't bloom from seed the first year, but also can't easily be divided or transplanted without destroying the original plant (and bettuerflyweed is really hard to move in my experience).

Good Luck.

If you find some small, first year butterfly weed seedlings, they transplant ok. The monarda will transplant, too.

For native seeds, I usually wait until they're ready, which can be at any time...Since I only have a suburban sized lot, it's fairly easy for me to watch individual plants or groups of plants, which is how I have the front yard planted.

For the little backyard prairie...I collect seed after the first killing frost, only because I have to wait until the frost kills the big garden spiders ;-)

Thank you for all the info. I'm going to need to take a second look at the St John's Wort in our field.It is
a Shrubby St John's Wort
that is native to Missouri and I guess the common is the one listed as a noxious weed in some states.
I'll make sure before I save any of the seeds.I may try

transplanting some wild bergamot. I was so excited to spot a couple of patches in our upper field but I was afraid to dig them for fear of killing the few that we had.