Cold Hardy Palm Trees species with cold tolerance thresholds:
Date Palm (Phoenix dactylifera) - (Date Palms are cold hardy to 18 degrees)
Needle Palm (Rhapidophyllum hystrix) Ė bush type palm cold hardy to -10 degrees, zones 5-10.
Canary Island Date Palm(Phoenix canariensis) - (Canary Island Palms are cold hardy to 15 - 18 degrees)
Texas Sabal Palm Trees (Sabal texana, mexicana) - (Texas Sabal Palms are cold hardy to 16 - 18 degrees)
Mediterranean (European) Fan Palm (Chamaerops humilis) - (Mediterranean Fan Palms are cold hardy to 5 - 15 degrees)
California Fan Palm (Washingtonia filifera) - (California Fan Palms are cold hardy to 15 degrees)
Windmill Palm (Trachycarpus fortunei) - (Windmill Palms are cold hardy to 5 degrees)
Pindo Palm (Butia capitata) - (Beautiful blue-green palms are cold hardy to 12 - 15 degrees)
Mexican Fan Palm (Washingtonia robusta) - (Mexican Fan Palms are cold hardy to 18 degrees)Donít plant above zone 9 without special protection. W. filifera is more cold hardy.
Queen Palm (Syagrus romanzoffiana) - (Queen Palms are cold hardy to 20 degrees)
The temperatures listed above are estimates.The organic program gives plants 4-5 degrees additional protection in many cases, plus reventative measures for cold protection can be used giving palms and other trees more cold protection.
Q: I have a variety of palms and they took a hard hit with the hard freezes this year. Had the trunks wrapped before the first hard freeze and are still wrapped. When should they be unwrapped and what about pruning and fertilizer to bring them back?
A: The hardy palms donít have to be wrapped at all. In your case, I would probably remove the wrapping because it really doesnít protect the tropical palms anyway.
Now (March) is the time to apply organic fertilizer and any of the locally available choices will be fine. Cut the brown leaves off, they are dead and wonít come back. Hopefully your plants arenít damaged too much. If you have to replant, the choices that didnít even have cosmetic damage include sabal, pindo, needle, Japanese windmill and Mediterranean palms.