A rooting hormone may help. I grow rosemary from primed seeds however.

The best cutting for woody shrubs like rosemary, is a heel cutting. I've always had good success with these, much more so than tip cuttings.

Forget spending money on rooting hormones. Pure honey does the same job, only better!

Here is a link that might be useful: heel cuttings

Angotja,
I have rooted rosemary by just taking a small tip cutting ( 3-4" ones have done best for me), without flowers. Oh, and remove the leaves from the lower part of the stem. I removed about half of the leaves in my cuttings and stuck it into the soil. Now its a 2 ftx2ft bush.

They were really easy to propagate but I am still pretty much a beginner gardener so what I have said may not even be the right thing to do! :)

Thanks
Mo

I had a Rosemary that outlived the half-whiskey barrel it was planted in. It had a huge central trunk. Every year I had to whack it way back to keep it shapely. I'd take the huge branches to friends. Once when several stayed in water a few days, they put out roots. Several friends planted them and they lasted several years. All this, when I had been told Rosemary wouldn't overwinter in this 7A climate. For me it was an evergreen. I lost it when the whiskey barrel fell to pieces and I didn't move rapidly enough to transplant it (it was huge and would have required another barrel, which I couldn't find in the fall.)

Mo - there's no 'right' and 'wrong' in gardening. There's only what works and what doesn't work - and even that varies with every garden and every gardener. Your rosemary grew, so you definitely did the 'right' thing.