My granny grew what we knew as "wasblommetjies" (wax flowers) on her veranda. I only knew the one variety, and was never even aware that there were others. The variety that she had is called Hoya carnosa and is common in South Africa. When I became aware of the diversity in this species I tried finding other varieties, but had no luck locally. I ended up importing a few rooted cuttings from the Netherlands without too much hassle, and they've been growing happily ever since. Since then other people started importing and collecting these plants, so cuttings of many varieties are readily available.