Pool sand -- be still, my beating heart.

I did indeed move the ricinifolia to another pot. I made a mix of 1/3 perlite, 1/3 MiracleGro moisture control potting mix, 1/3 pool filter sand.

It has turned out to be very fast draining, but it will be a good experiment. Hopefully there is enough peat.. one thing for sure, the rhizomes of the begonias will probably not rot in this sandy mix. 

This is from a twig of U402 ( unidentified species begonia) that's grown huge under the bird of paradise. Happy as a clam.