I think I may have asked this in an earlier post, but I'm still not clear. It's getting late in the season here in Vermont, and I want to be able to take cuttings from my mandevilla vines. They are currently potted on my deck growing up trellises. Will their cuttings root in water? If not, will they root in rooting hormone? I have not had sucess with any plant using rooting hormone, so is there anyone who can give me real simple step by step instructions on that? I'd rather use water. Much simpler.