This year I'm potting up wildflower seeds early so they can sit outside and sprout whenever they feel like it. Pots can be worked far earlier than the ground -- if I keep the potting soil indoors so it doesn't freeze solid.

I have lily bulbs from a few years ago potted on the back patio. It doesn't get cold enough here to freeze the ground so they get to hang out back there. There's also some potted mints of various kinds that have self-seeded and coming back. :D