This is a Choisya ternate. You can propagate from 3" cuttings taken in August but I am not sure about layering. If you try it you have nothing to lose. Perhaps when you do it you might try cutting a small nick in the bark on the underside of where you want it to root. Good luck.
Thanks Woodhams, maybe I'll try the cuttings instead as it sounds easier for an amateur
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