I dont really know, but i have used transparent glasses to root Hydrangea cuttings.

Thanks Julien,
I would try some and some, but I've only got 5 precious little cuttings!

don,t think it makes much difference really, iv'e always used old jars with no probs. but it is advisable to pot them up quite quickly as you see the roots form as they are easily damaged

Sometimes the roots form more quickly if light is reduced in the water, but I would just wrap the jar in foil, so it's easier to inspect frequently.

Thanks Kev, if they root I'll pot them up immediately; thanks Tug, that's a simple solution!

Your welcome!