Hi there, if you click on the link below to take you to a recent thread I started and read through the posts and almost at the end you will see someone else asked me the same ? about how I got my Sabal Minors to sprout. My method works well for my palm seed experiments and many other hard to germinate seeds that need that extra bit of heat not provided by our UK climate, especialy at this time of year. Good luck!
Gill.

Here is a link that might be useful: germination