I pull up dozens, maybe hundreds of volunteer marigolds every year and let probably 2 dozen grow. There are thousands of seeds still on the plants now.
Sometimes flowering tobacco reseeds here. Daturas do well too. Too well really.
Cardinal vine reseeds well in central U.S.
Zabrina Althea reseeds wildly too.
Vining milkweed reseeds and is very pretty and fragrant.
Just a few I can think of at this time.
