The USDA hardiness zones map got updated.
A newly updated government map has many of the nation’s gardeners rushing online, Googling what new plants they can grow in their mostly warming regions.
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My zip code apparently doesn’t exist. 
Same. For now the graphical map displays but the zip code lookup search box is broken and needs some tech folks to look at it.
It’s pretty useless anyway. I’m in the same zone as southern Texas and Florida which seems funny considering my July highest temp was 65F.
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It’s a basic guide.
From someone in Texas I can say the daily spread between highs and lows is a very significant factor in what can or not grow or thrive in a given area. Oklahoma and Texas are some of the most difficult to grow-in areas due to the large spreads between very hot then very cold temperature swings sometimes within a single day. Additionally, the overnight temperature drops in the summer time here are practically non-existent so plants don’t shut down their transpiration during the night hours adding even more stress.
I am the same zone as North Carolina where one of my favorite gardener channels lives and I can’t grow 90% of the plants or grow as successfully that I see shown on that channel.
Interesting.
I don’t know that it changes a whole lot for me since I already knew that I was right on the border of two zones and was willing/interested to see what I would be able push to grow here that says it’s for 8a anyway.
Now instead of being marginally on the side of 7b, I am shown as marginally on the side of 8a… I’m not sure how meaningful that really feels. 
Yeah, one of the things that never seems to stop shocking me even though I know it’s like that in other places, is how much the temperature drops at night whenever I travel somewhere else - or in the couple of times when I have moved somewhere else.
Thanks Peter. This is interesting. According to this new map, I am about 10 miles north of the 8b/9a border. I still have 2 watermelons on the vine!
I do think the hardiness zone is interesting but really lacks depth. I think knowing the average frost frost date is the crux of the value being put forth.
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Circling back the zip code search function worked for me now when I tried it today.
Consider looking into the Koppen system. It has more criteria and to me it’s use is not intuitive, but it’s worth a try.
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Haha wow… and I thought I was close to the edge. Before the recent update, the map was drawn in such a way where our home is in one hardiness zone and our kids attend school in a different hardiness zone.
With the update, it should all be the same zone now, but we’re still not very far away from the other side of the line.
I’m sure a little microclimate here or there would make more difference for us than where that line on the map is.
Hmm… I’d never heard of it, so I was curious to give it a look. But the map i looked at has me in this massive yellow-greenish blob that goes beyond the northern border of Oklahoma (they get often significantly colder than us), extends to much of the western part of Oklahoma as well as Texas on down west of San Antonio, down to the southern tip of Texas, includes the entire US Gulf Coast, goes back up much of the east coast to Atlantic City, and looks like it snags Philadelphia…
I can’t say I have ever imagined Philly to be the same growing conditions as Abilene… but then if I am entirely honest, I have never actually tried growing anything in either place, so what do I know 
FWIW, this is the map I was/am looking at in case I am misinterpreting something or it is messing up:
My zip code has gone from 5b to 6a. Who knew, the climate is really changing.
It claims my zip code is 5b, which is definitely not the case . . . it hasn’t gone below 5 degrees F in over twenty years! (Except for in the massive Arctic storm this February where it hit 3 degrees F for a few hours. People all over the country got temperatures colder than their average zone that night.)
That makes my zone 7b. Or 7a, if you want to count in the freak storm, which I don’t.
Maybe there are other parts of my zip code that are only 5b?
Forty years ago, my town was 5b, but it really hasn’t been for a long time.
It moved us from 3b to 4a which doesn’t much change my gardening plans, but probably does portend serious changes over the next 100 years to the native forest.
That’s true. But . . . all three of the fig trees I planted last year were only hardy to zone 7b, and all three of them survived just fine. They had no protection; I hadn’t even mulched them. They were completely exposed to the cold and the wind. That implies that it probably didn’t go below zone 7b temperatures in my yard, even though it did at the weather station on the other side of town.
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Also if the temperature was really only that low for a few hours, it wouldn’t have dropped the soil temp nearly as far even if it did hit that temp measured directly on your porch.
One of the problems with the new climate data is that in many cases they kept the same location for the meters but didn’t adjust for the fact that those locations are now in a city, often on concrete or in concrete canyons rather than in open fields.
Changing circumstances lead to changing microclimate, which throws everything off.
In other circumstances they’re using airport meters, which theoretically should continue to have the same conditions, but the meters have been moved within the airport to make room for construction projects. Stick one in the sun that has always been in the shade, boom, growing zone leap.
Standardization plays a similar role. If the meter was 20 feet up a radio tower and now it’s at the standard height, it’s going to take 20 years to adjust back to normal.