Every Fall I cut back my Tropical Hibiscus - H. rosa-sinensis and keep some of the cuttings for
insurance. I spent about an hour this afternoon potting up the cuttings that rooted - the time it takes for them to root has been pretty consistent over the years, about 2½ to 3 months. I use fine vermiculite for the rooting medium and cell flats, no rooting hormone and get about a 85% success rate on roots forming and about 10% that don't root but the cuttings are still viable. The cuttings stay in the greenhouse the whole time and are subject to the fluctuating temperatures .. Around the end of January is when I pot up the rooted ones and the viable unrooted ones (on the right in 2nd picture) in potting mix.