Have you seen the new USDA hardiness zone map? It's pretty neat, moving me from 6a to 6b. It's hard to see subtle changes until you use the interactive feature and search by zip code.

http://planthardiness.ars.usda...

Karen

Yes, it's definitely time.

I stayed the same

This is a lot more detailed! I wish the data set was freely downloadable. It's extremely expensive to buy the whole thing.

But at least the website has lots of really nice interactive features. You can zoom into your own neighborhood, even.

I moved from zone 8a to 8b.

I moved from zone 6b to zone 7a.

I am still in zone 9b. I liked being able to enter my zip code and get the exact zone. I still prefer the sunset zones and descriptions over USDA.

It really is a nice map. But I think in some cases, certainly mine anyway, it's really necessary to use the interactive feature to fine-tune it to your own area.

Try it if you haven't!

Karen

I always used the Sunset zones when we lived out West. I still have my Sunset Western Garden Book. I think I have about half of it memorized so can't give it up.

Yes, when I started gardening here, the Sunset Western Garden Book became my gardening bible. Could always count on it to tell me what plants really grow in this desert climate. Unlike the folks at almost any nursery.

Agreed.

I'm still in the same zone but more so. I was near the line between 9a and 8b. The line was only about 3 miles north of me now it's about 40.

Hah! 8b.
I've been living the life of a 7a gardener!
Thanks for the tip!

It's good the USDA is updating to reflect reality. I moved a half zone warmer Global warming?

me with my zone envy, I am still at 9b I so want to be zone 11

jmorth said:I moved a half zone warmer Global warming?

Or alternatively, the information used for compiling these zones is more accurate now than it used to be.

Hum, I'm in 13b.
.

I always knew I was more in the zone 6 range than 5 and now the chart shows it correctly.

I see that the map is based on average annual extreme minimum temperature. I wish there was an update that gave information about average first/last frost. We've certainly chaged from what it used to be. The challenge is increasing variability in extremes.

The National Climatic Data Center tracks freeze/frost dates for the entire United States and releaed sometime ago the complete data from 1970 through 2000. That data is freely available but is in a computer readable format.

A long time ago I wrote software to read it, parse the information and present to the user their own local frost dates information. I should go back to the NOAA site and see if I can find that data again, maybe I can make this a feature for ATP.

Ahh, here it is: http://cdo.ncdc.noaa.gov/cgi-b...

The raw data is this: http://cdo.ncdc.noaa.gov/clima...

Raleigh Durham airport is:

90% chance of a frost before March 25th.
50% chance before April 10th.
10% change around April 25th.

For last dates, RDU is:

90% chance of a frost by Nov 10th.
50% chance by Oct 28.
10% change by Oct 14.

I am further into zone 6a. I will still get plants rated for zone 5 , zone 6 plants have always been iffy for me.