I would skip the water and just put the cuttings straight into a fast training seed and cuttings mix.

No matter which method, you can take about a 4-6" cutting and strip off the leaves from the bottom 2-4".

You can use rooting hormone at this time or not.

Stick that into your water or growing medium. Put in bright shade or indoors with some light (I use my kitchen window). After about 2-6 weeks, it will probably root.

If you do it outdoors, you can either keep the soil consistently moist or use the plastic bag method to have some humidity for the cuttings.

As you say, you have a large plant with many good branches to use. I would do about 5-10 cuttings at a time so that you can increase your chances in the same time period.

There may be a few stalks that just die or begin to rot. Once you detect that those won't have a chance, go ahead and toss them (trash or compost pile).

I have done it by water these last 2 years for many cuttings, including some going on currently that have about 1-2" roots (visible because I'm using a plastic transparent cup). I will eventually pot them up and keep them in shade until I see the plant is not wilting or dying from the transfer to soil mix, so about 7-14 days.

My mom did it also using her own garden soil in black pots. Neither of us used rooting hormone.

It just means there are many ways to achieve the result.

This post was edited by gardenper on Thu, Apr 24, 14 at 10:51

Layering may work. Being somewhere rosemary doesn't overwinter, I've never had the chance to try it but it is what I would try. Look up "layering propagation" at google for more info.

FataMorgana