Texas Mountain Laurel from Cutting?

I have read that it is very difficult to propagate TX Mtn. Laurel from cuttings and, from my attempts, this is proving to be true. Does anyone have any experience successfully rooting them from cuttings?

I may try air layering next year to see if that works any better.

I know there are cultivars available like "Silver Peso" and "Silver Sierra" as well as white flowering varieties. I'm not sure if those are grafted or rooted on their own roots.

I was gifted the rooter pots rom Lee Valley Tools which work very well.  The water reservoir in them may stimulate root development during drought conditions though spring growth is recommended.
I used them to clone tomato plants but that is easy.