I've read that it's possible to grow herbs like mint and basil in just jars of water, and articles like this and this seem to suggest that rooted cuttings can thrive in just water for a long time (the author in the first link mentions 6-12 months in the comments). However, I find in my attempts that no matter how clean my tools and water are, the wounds on the cuttings (where I've made the cut, and where I have removed leaves) begin to turn black and rot within a couple of days of being submerged in water. I have been changing the water every 1-2 days. My cuttings now have roots, but the rotting is still progressing, and I will probably have to pot them soon to stop the rot taking over.
I was wondering if anyone has had success growing cuttings in still water for more than a couple of months, and in your case, what did you do to stop the rot from developing?