One website claims it can survive from zones 7 - 10. Yet another claims that it won't survive below 40 degrees. This is not true. I've had it survive into the low thirties, and if I remember correctly, even down to 30 degrees.
llifle (one of my trusted C&S sources) says it's hardy down to zone 7.
http://www.llifle.com/Encyclop...
