I received Hoya greenii growing in a very light weight mix, and it was bone dry when I unpacked it. I immediately watered it, but the water ran right through it. I decided to leave the plant in the mix that it came with as the plant looked so phenomenally healthy. The soil mix seems to be comprised of slivers of bark (Fines?) and small perlite. I found that I need to water the plant every two to three days to keep it happy.