Answer: The following web site asks for your zip code and then provides the USDA zone you live in:
Sunset's Western Garden Book also includes extensive zone maps at the beginning of the book. Note that they use a different system than the USDA, but it allows for more variation in the West's climate. Their plant listings follow their zone numbers.
Chiltepin seeds can be ordered from Native Seeds/SEARCH in Tucson, which supplies native and heirloom seeds for the desert. Their web site is: http://www.azstarnet.com/~nss/
You might also call some of the local specialty nurseries such as Bakers Nursery or Berridge's Nursery. Look under Nurseries in the Yellow Pages. They often carry a wide selection of seeds. Good luck with your chiltepin seeds! The plants take alot of abuse and keep on growing!
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