You can, although not the easiest method of propagation. And the timing may not be overly conducive (best in summer with half green wood cuttings - new growth that is just starting to ripen). There are lots of how-to's online you can refer to but I would encourage rooting in soil rather than water. Roots that form in water are morphologically different from those that form in soil (they are adapted to obtain oxygen from the water, which soil roots cannot do) and they do not always make the transition from water to soil easily.

What you say makes a lot of sense: that rooting from last year's woody cuttings might be difficult.

They are already in water now so I'll just leave them as a science experiment. Then in summer I'll try with new wood cuttings.

Do you think post-bloom would be best?

I actually have a mix of perlite and peat (and I think something else that I've forgotten) that someone on Gardenweb suggested for rooting woody cuttings for a houseplant I wanted to propagate. That worked very well.

Thanks again.

" Do you think post-bloom would be best? "

Early to midsummer, regardless of bloom time. You want semi-softwood cuttings.