Have you tried air layering? I tried propagating Lilly Pilly several different ways without success, until I air layered a couple of branches. It worked. I’d either try that or drag a branch down to the ground and cover part of it with soil. I have been having difficulty propagating my feijoa, so will try air layering next. I was told they’re easy to propagate 🙄 not in my experience. If I ever have a stubborn plant I want to propagate, this is the next method I use.
