Neal ...
Thanks for the information about the Ca. poppies.
I was guessing that since the plants were creating seed pods in spring, or early summer, they were ending their natural cycle and if I interrupted that cycle as we do when we dead head roses, the plants would naturally attempt to create new seeds.
I haven't tried other kinds of poppies, and may purchase some seeds this year. Right now, I am trying to figure out what bulbs will work and where to put them.