You know when most people say that, it means that one winter finally came and got them and now they realize why it is that they are indeed in Zone xx. Well, haha! I was right and NOT in zone denial. The Zoning authorities were. Since I moved here I have thought again and again that despite my Zone 8b official rating, I am in Zone 9a. Not so much by what freezes here in the winter, but what WILL NOT UNDER ANY circumstance grow here through the summer. You of temperate zones might not notice, but many many many garden plants end their 'hot' zone at 8. Now technically Plant zones really are more about the freeze, but still, I have been extremely suspicious.
And now, all I can say is: I could have told you this three years ago. The peninsula of downtown Charleston is in zone 9A. The new area plant zoning map:
Sure, its the world's smallest zone area ever, but I KNEW IT! Plus, in 3 years, including one of the top 10 'coldest' on record for the area, my yard never got below 26 degrees. Last year the lowest was 32. Only for 2 days. SO there! We are regularly 5-10 degrees warmer at night in both winter (yay) and summer (ugh horrible), than 5 miles in any direction from home.
Now I have go tell all the lemon trees and brugmansia trees around town the news so they stop having to justify their existence.