25 cents a petunia in NYC! That is cheap! It's good to know NG impatiens can be rooted with water.I have never been successful overwintering impatiens except maybe Fusion once. I don't remember if it was worth it for me but a relative does them all the time with good success. She treats them like houseplants by the window during the winter.
I've done many of the plants Tiffany has. Also geraniums, pentas, abutilon, shrimp plant, ginger. I've also taken cuttings of salvias, geraniums. I bring in tender herbs like lemon verbena, bay leaf and stevia. I haven't been so successful with the needled herbs like rosemary, lilac and curry. Some plants like mandevilla, spanish lilac and gerbera aren't worth the rebound time in my case. Some always get infested before winter is over. I don't take salvia cuttings anymore because they always have whitefly that gets out of control indoors. This year I am going to try their roots.