hours of pelting rain, strong winds, and now a beautiful huge door-side hollyhock that had grown up in a crack in the paving has blown down--all three stalks, despite attempts to support the last two.

Can a new one grow from the remaining root?
Can I save seeds from a plant that had only just come into flower?
plant the brokens stalks?
No answers from a short google search, so if any knows, I'd be glad if info.