Time it takes to root has less to do about species than it does about time of year, method, warmth, day length... With the days getting longer, they root quicker than they did a month or two ago, and since you're in a warmer area, that will help, too. Some of it depends, too, on how old the growth was that was cut - older, woody growth takes longer. Most of my Hoyas take about a month to get some roots going this time of year. By the end of April, a lot of them take far less time.

Denise in Omaha

I bought a H. lauterbachii last year. It was grown from a cutting and nearly half a metre long. So I cut it in half and gave the top to a friend in a ziplock plastic bag (2 for the price of one, LOL). She told me it was putting out roots after about 2 weeks. The temperatures then were mean maximum 29C daytimes, and mean minimums 19C nighttimes. So that was with a piece of new growth.