USDA Zone chart

The USDA Zone chart indicates lots of zone 7 property out there. People in zone 7 now easily grow oranges, pistachios, figs, pomegranite etc.


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Must be nice! They put us now as 6a but I’m afraid no way that is right we are still 5b.
At least if that chart is right.

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Same with us but the opposite we are shown as 5b but are supposedly 6a and some years we are warm enough to be considered 6 a.

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Yes some years us too. I’m fairly happy living here though. I may move south all the same. Time will tell.

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Here is an actually usda map which looks much more accurate

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90% of Ohio is zone 6a, but I’m in a little speck of zone 5b.:slightly_frowning_face: We still can see the occasional minus low 20s, but didn’t even come close to zero so far this year.

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Based solely on 2019/2020 we are zone 8 for sure in Kentucky! Palm trees and Oranges, here we come!

However, I have seen minus 29 in 1960, and minus 30 and minus 31 since then. And driving on Lake Cumberland in 1977.

January 2014 ‘removed’ about half the LELAND CYPRESS trees in eastern Kentucky and made crape myrtles sprout back from the stumps…at -19.

That’s how you get an “AVERAGE” temperature as zone 6…you average the years of 15 degrees with the years of minus 20 degrees. (And they did move us to Zone 5 after the 77 and 78 winters…for a decade or two).

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That’s funny, our zone here goes up and down between 7a to 8b, so anything that is permanently going to be in the ground, has to be able to handle zone 7a, those charts even the USDA one should not be taken seriously unless you are growing something that dies every year anyway.

Some oranges that are edible can actually in be grown in the ground in zone 7b. Yet often our temperatures goes down to 7a, it’s becoming normal to get 3 degrees Fahrenheit here every now and then.

Flying Dragon bitter orange are zone 6a, yet I have no reason to grow that for fruit.

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You can look via zip code too.

USDA Zones

Mine says 8b. However, I can’t imagine growing oranges here. Mexican Fan Palms grow nicely here but probably not date palms.

Last year I left my potted Meyer lemon outside, thinking that might kill it. It survived and is actually doing very nice now.

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Zone ratings SHOULD account for that. Something rated for zone 6a should be able to at least occasionally handle closer to -20°F. Otherwise it’s dead in the first colder than average winter.

Certain nursery and seed companies push them so much that they use this logic:

Zone 5 is -10 to -20. This plant is hardy to -8. Round that up to -10. Ok, zone 5.

Really that’s a zone 7 plant.

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It says I’m 6b which is pretty accurate most years for me (sorry, Drew). This past winter, however, I’m willing to bet I pulled off 7b!! The coldest I measured (and this is supported by the weather station at Detroit City airport 9 miles south of me) is only 13 degrees. We hit this temperature on 3 different occasions this winter.

Scott

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You are dreaming if you think you can grow any edible citrus outside in 8a or lower zone without repeated freeze protection. Citrus/fruit trees don’t freeze due to the average low temperature, rather the absolute low temperature and duration of the freeze. A few hours of 10F kills all citrus. After all mangos can be grown in Seattle based on the average low temperatures. Ever seen one growing outside?

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That chart lists me as 4a. We hit -38 here last year and numerous people I know in the general area had -40.

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Those charts seem outdated. The one goes through 2005. The ice age before global warmings :slight_smile: I thought I had seen a much more updated chart. But, I guess they still have to sketch them out with pad and paper.

The old charts had me in 5b, but our average temps over the past 20 years have been in the 6a range. This chart from Arbor Day up to 2015 is more accurate for my locale but surely bad for other areas.
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I can assure you that much of northern WI, as well as central and northern MN is not zone 4

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@mrtexas
I believe you might need to throw a blanket on them at times. Think you might like this article http://www.appalachianfeet.com/2012/02/25/how-to-grow-tasty-citrus-outside-in-zone-7-tangerines-grapefruit-oranges-more/ . Texas like Kansas has extremes.

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What is intereeting to me (and this is in no way a “climate change denial” thing), is the REALLY OLD zone maps were warmer than the 1990 map. At least in Ohio where I grew up.

I recall a very old map in the 80s…they had Zone 7 almost touching Portsmouth, Ohio. Then the 1990 map put most of Ohio in 5 or 6. The 2005 map now puts almost all of Ohio in 6. So they were warmer, then colder, then warmer.

Ok. So I don’t know about the “really old” map. But per the USDA, the 1990 map only included data from ‘74-‘86. They were some very cold winters during that time frame in the mid western and eastern US. I believe out West had some doozies during that time as well. In fact, save for a couple years in the ‘60s, that was probably the coldest set of years in the 20th century you could’ve chosen as far as ultimate winter lows.

The ‘05 map uses ‘74 - 2005.

https://planthardiness.ars.usda.gov/PHZMWeb/AboutWhatsNew.aspx

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Good luck. Lol, I grow all those here in 9B. Be prepared for disappointment in Zone7

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Three maps…1960, 1990, and 2012.

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My current home was zone 7, then 6b, now back to 7a, although pockets of 6b are close.

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Over the years, at times there has been some reluctance to release some climate related maps in a timely fashion for political reasons. I assume that the USDA zone chart had been one of the less political maps until now with the talk of climate change (when has the climate not been changing?). Maps related to vegetation/grassland productivity might not be released because they could potentially affect ag/tax valuations or crop payments. That’s unfortunate because i find all of it interesting.

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