John S. DeBoo wrote:
I'm in Albuquerque which I'm told is zone 7, and looking in a few
books they too show zone 7 (large US maps). However I snagged a
copy of Sunsets "Western Garden Book" from the local library
Saturday and it shows me in zone 10 (state map and of course more
detailed than a US map). Could this be an error? 3 zones is an
awfully big discrepancy. It doesn't show a 7 in the entire state!

Before you ask, No, I've not contacted a nursery - YET - since
reading this as I just ran across it an hour ago.


http://www.usna.usda.gov/Hardzone/ushzmap.html


If you look in the beginning of the Sunset Western Garden Book, you'll
see an explanation about how their zones differ from the USDA zones.
(USDA zones are the standard.) Essentially it comes down to this: The
USDA zones are based solely on the expected normal low temperatures of
winter. Sunset, which if I remember right uses 24 zones (plus
subdivisions) for just the western states compared to the USDA's 11
zones (plus subdivisions) for the entire country. They attempt to use
their zones to describe summer highs, as well as humidity and such.

However since the USDA map is the standard, the Sunset zones are
generally only useful if you're reading Sunset magazine, or one of their
books. It may be a much better system, but it's still non-standard. It
would have been nicer if they had used letters instead of numbers for
their zones to avoid confusing novices who haven't read the fine print.

--
Warren H.

==========
Disclaimer: My views reflect those of myself, and not my
employer, my friends, nor (as she often tells me) my wife.
Any resemblance to the views of anybody living or dead is
coincidental. No animals were hurt in the writing of this
response -- unless you count my dog who desperately wants
to go outside now.