Any info would be appreciated. Thank you all.

Plant Hardiness and Mapping Out a Strategy
by Tony Avent, Plant Delights Nursery, Inc.
updated 12/30/07

Good Maps Gone Bad
"............ the American Horticulture Society made an even bigger horticultural faux pas when, in 2003, they published a draft revision of the 1990 Hardiness Zone map. It's called a "draft" version because interested parties notified the USDA about the impending screw-up just prior to publication, and the project was halted immediately. The 2003 draft map, using data from 4,700 weather stations, was compiled using the premise that the climate had warmed so dramatically that only the last 15 years (1987-2001) of climatic data was needed. This recent data shifted Chicago, IL, into Zone 6, making for a true horticultural disaster when a real winter such as 2002/2003 occurred. The 2003 map also eliminated the "a" and "b" designations which would put two completely different climates, such as Wilmington, NC, and Wilmington, DE, into the same zone. This change was being made to make the map more "readable." The 2003 map also added more tropical zones, 12-15. The 2003 map certainly tops the all-time horticultural "what were they thinking?" list. In 2006, the Arbor Day Foundation released a map similar to the 2003 AHS map, which made the same unfortunate errors in judgment by including only 10 zones and using a 15-year dataset.
New Maps on the Way
On August 18, 2004, a group of stakeholders first met at USDA-ARS offices in Beltsville, Maryland to discuss the 1990 USDA Plant Hardiness Zone Map revision. The August 18 meeting included representatives from USDA-ARS, the American Horticulture Society, the American Association of Botanic Gardens and Arboreta, university researchers, and representatives of the nursery industry. There have been several meetings since, as work on the new map progresses. In 2007, the contract to produce the new map was awarded to the Prism Climate Group from Oregon State University.

The hardiness map revision project will consist of two phases. In Phase I, the map will be reconstructed using the most recent 30 years (up from 15 years) of average annual extreme minimum temperatures. The map will also retain the "a and b" designations for zones 2-10, but not for zone 11 and zone 1. For the first time, the map will include a better breakdown of coastal/lake effects and elevation differences. The map will be made available on-line where you can search for and zoom in on a target area. The map is nearing completion at the beginning of 2008. Preliminary draft maps show many areas that have warmed up to 7 degrees from the 1976-1990 period to the 1991-2006 period. Other parts of the country have seen their average minimum temperature rise only a degree or two. Final details and concern of the committee are being addressed at this time. Phase II of a possible future project will hopefully involve overlay maps for other factors such as duration of cold, summer heat factors, and perhaps even air flow patterns.
Summary
What I hope you will realize is that growing plants can be very complex. The hardiness zone maps are a great guide, but are only a guide and only when the zones assigned to plants by nurseries are accurate."