Last autumn I rescued some rose bushes from a bin and they have taken really well and look very healthy. Right in the middle of one has grown a beautiful deep purple aqualeiga which must have come in with the roots on the rose. It is too entangled in the roots to move so I will let it grow where it is; but I would like to propagate it. I have been told that seeds wont come true and it will revert to pink. So what should I do. Take a cutting of some description?