Alan is recording what happens at HIS house. He may get the freezing temps while your area is spared; conversely, you may get conditions that cause die back while he does not. In addition, you may have microclimate zones that protect your area from light frosts but which will still freeze from more serious weather.

A microclimate is an area that usually has some difference (perhaps due to a wall or adjacent trees/shrubs - or lack thereof) and allows that area to act more like a warmer or colder zone.

Here is a link that might be useful: Microclimate definition

Okay, thanks..I know he's recording what is at his house, but I wasn't spared the freeze here either. But, the micoroclimate thing you mentioned may have something to do with it; I have a large yard but it is surrounding by trees and at the first freeze last year (Nov) the trees had just about fully dropped all their leaves but at the first freeze this year (Oct) the trees are still fairly full - so that fullness may have added an 'insulating' effect down here in the yard. Makes sense I guess...and not much I can do to control it year to year...thanks again for that link, very informative.

Well my cannas are toast, as was my wandering jew that I forgot to bring in.

But even in my yard, in the front, the lantana turned brown and lost it's flowers, but didn't in the back. So it depends.

It also could be that the cold temperature this year didn't last as long as last years first frost and therefore didn't damage the cannas.

I will ditto esh's comments. I am always amazed at how microclimates affect individual gardens.

What's the difference between a frost and a freeze? Frost occurs on a clear, still night, as heat radiates from surfaces (your car window, a field, etc.) to the sky. The temperature drops below 32 degrees, and water vapor freezes on those surfaces. The temperature usually won't go much below freezing, because energy is released as the water freezes. Most plants that aren't tropical can go 2 - 3 degrees below freezing with no problem. Heat will be trapped by any overhang, so tender plants will usually not freeze if they are up against the house. Clouds or fog will trap the heat, usually preventing a frost. A freeze is when cold, Arctic air moves into the region. The air is much colder than freezing, there is wind, and the humidity is very low. Much of the damage we see on plants in a freeze is from desiccation--severe drying of the foliage. An overhang provides less protection; sheltered plants may need to come indoors.

I would guess that the presence of a canopy prevented frost from forming this year. Good Siting!