I have a small ivy. Well, it started out small. But it's gotten to big for its pot and some of the runners have died. So, I took some cuttings off of it and repotted the rest to spread it out (all of the plant had moved itself to one side of the pot. Anyhow... I am trying to root these cuttings, but it's going VERY slowly. Is there anything I can put in the water to help it root more quickly? Or should I put it in a certain kind of container? Right now I have them in a wide mouth glass vase so I can watch the progress.