Does anyone know how to root this vine/shurb? Will it root by water or soil? What part of the vine do I use to get it to root? I know not to use the totally green soft sections. I have been using slightly woody cuttings. But not old 'woody' parts.

I have had no luck getting any rooted cuttings. I see what looks like those white 'root bumps' appear on stems in water, like on Brugmansias cuttings when I put them in water. But they never get past the 'stubby stage'. Is this the best way to root them or is there a trick to get them to get past the 'stubby' stage? Any hints?