For my Purple Alocasia

Does anyone know a mail order source for lava rock that I can use in potting my temperamental purple alocasia. Every winter I have rot to many of the alocasia. I use perlite (a lot of perlite) and some Jungle Grow potting soil. I added bottom heat from a bed with sand and heating cables but I still have rot on some of the alocasia. With the heat, all of they have not been going dormant-at least most of them remain growing or at least not dying. I hold back on the watering. I have read that the Lava rock (tiny) works well.
Every year I try something else in hope that one day my alocasia and I will come to an understanding-no more dying on me!!! Yet, there appears to be something wrong with me-I keep buying these temperamental plants.
I would really appreciate any help. Thanks
Barbara

The lava rock should be available from any supplier that carries hydroponic supplies. There are a number of them and most likely one in your state. Also, don't hesitate to check the Garden Watchdog once you find a potential supplier(s) so as to see how well they take care of their customers.

If for some reason you still have trouble finding it, a good substitute would be an orchid mix. The way these "jewel" Alocasias grow in the wild is that their roots are getting extraordinary aeration because of the loose substrate they are growing in (twigs, leaf litter, etc.) They are not found with their corms buried in moist or wet soil. Some roots may make it into the top layer of soil, but most of it is getting lots of air, even in the rainforest.

LariAnn