I just planted the java fern in rockwool and net pots, I set the rhizome on top of the rockwool with a couple roots in it to hold it down, it has since spread its roots and started shooting up new leaves, here are some pics. If this method works well, I'm going to try and obtain some harder to find varieties of java fern and grown them this way as well.
Thanks for the speedy reply. Do you think this would work if the rockwool was replaced by potting soil? I am trying to figure out the best way to grow mine.