Kevin,
Wikipedia notes on the "Hardy Palms" page
http://en.wikipedia.org/wiki/H... 'There are also a plethora of mature T. fortunei growing unprotected in downtown Washington D.C. and surrounding areas. Most notably 15' tall tree in front of the National Air and Space Museum, since 2001.' One nursery near me has had a 7-8' specimen for 4 yrs. or more. Heavily wrapped in winter of course.
