Jonna, I tried your vermiculite method for begonias last year and was a total failure. They stayed so tiny for so long that I wasn't able to prick them out and transplant. They sprouted like crazy but most just turned yellow and withered away in the vermiculite.
begonias
The echinacea worked great with the vermiculite. They're much bigger, faster growing seedlings and I was able to handle them.
echinacea
Karen