Weatherproofing a Palm Tiki & Installing

So i finished carving a 5 foot palm tiki and i i want to put it outside in the elements. it doesn't rain too much here in AZ, but would some thompsons water seal do the trick?
Also, i left about a foot at the bottom for install, but i'm not sure the best way to install securely without putting some of it in the ground leaving it open for rot.
Thanks for your comments!

JD, If I remember correctly, Tucson Tiki or Jungle trader told me to give my efforts a coat of spar varnish or something similar. I'm down here in Tucson, so same climate as you. Hey, Thompsons might do it, but wait till one of the 'masters' like Benzart or Seeksurf or Jungle trader or Tucson Tiki or others reply. Might check out the search feature too.
Ciao

[ Edited by: drgoat456 2009-03-10 11:36 ]