I am not coming up with any specific planting instructions in my research, but I would suggest leaving the top part out of the soil if I were planting it without more positive instructions.

Phil

Here in Volcano, we plant hapu'u partly buried. Make sure it is shaded. It normally grows as an understory plant.

Hi - Thanks for the tips and info. I replanted my tree fern with about 1/2 above the ground and placed it in a shadier area. Now lets see if it will grow here in Arizona! it might if my dog doesn't keep thinking its a football. -- Michele

In Arizona, you may want to try full shade, no wind and near some sort of water to moisturize the air. If you happen to have a sheltered courtyard with a fountain in it, that would be a good spot. An australian tree fern would perhaps be a better choice for a fern to grow in Arizona since they don't mind the sun and wind as much. Is there anywhere it can get high humidity?

Your Hawaiian tree fern is either Cibotium glaucum or C.chamissoi (the 'splendens' tag is a nurseryman's misnomer applied to any damn thing). As for planting it in Arizona: virtually impossible, I'd say. In theory you can grow anything anywhere, given enough equipment - after all, NASA have experimented with horticulture on the sea bed and in space - but for all practical purposes Cibotiums in your part of the US are outrageously difficult. Only by enclosing the tub in an enclosed, shady, high-humidity environment will it be possible - and even then, how will you keep the temperatures from soaring? Some kind of shade-cloth tunnel - polytunnel hoops draped with mesh - would be the only way I can think of, and you'd need to build in almost continual automatic irrigation and misting. Otherwise the poor tree fern will fry in the Arizona heat and desert-like aridity (to be brutally honest, it would be easier to keep Cibotiums in Alaska).

Unless you're up for a shade-house, or some equivalent solution, your Arizona Cibotium experiment will be short-lived indeed. Whether to bury the trunk or not* isn't really the priority.

Steve - Brighton, UK

*In case anybody's interested, all tree fern trunks require only minimal burying when potting up - just deep enough to get them to stand up safely without risk of toppling over. In the wild, Cibotiums habitually fall over and then re-sprout along the lenth of the prostrate trunk.