[Lore]

Finally after over twenty years the USDA has updated their plant hardiness zone map. The new map shows a pronounced shift to the North in warmer growing zones among many areas of the country.

In my area we went from zone 5b to 6a. New interactive map follows.

http://planthardiness.ars.usda.gov/PHZMWeb/

[PrestonSturges]

Sometimes a fairly subtle shift in climate can bring in new diseases, like apple rust.

Some people might see specific varieties of plants crap out in the heat, but a bigger concern might be the early bearing fruit varieties that won't stay dormant in a mild February, then slammed by a late frost.

I like the jujubes becaue they won't bud until long after the last possible date for frost, then they love they heat.

[Tanada]

On the one hand I am glad they finally updated it, on the other hand I am puzzled. Normally the map is a 30 year average going from for example 1961-1990 while this map is 1976-2005. I know certain parties refused to update the map to 1971-2000 when it was due to be updated but I kind of expected this one to be 1981-2010 not 1976-2005. Basically all they did was take the Arbor Day zone map of 2006 and make it official. http://www.arborday.org/media/map_change.cfm

My zone has also shifted from 5 to 6, so less harsh winter temps.

[Pablo2079]

These maps are only marginally valuable.

If you compare a zone 8b in Washington state to a zone 8b in Texas, the types of plants one can grow are wildly different.

[dohboi]

Does anyone have a link to the previous map?

related link:

http://www.usatoday.com/news/nation/environment/story/2012-01-26/USDA-climate-zone-map/52787142/1

[Loki]

Does anyone have a link to the previous map?

related link:

http://www.usatoday.com/news/nation/environment/story/2012-01-26/USDA-climate-zone-map/52787142/1

http://www.arborday.org/media/mapchanges.cfm

Animation shows the change in zones.

Another display:

[Loki]

These maps are only marginally valuable.

If you compare a zone 8b in Washington state to a zone 8b in Texas, the types of plants one can grow are wildly different.

True, the USDA zone map is only average annual minimum temperature. Important factor for plants, but not the only one. There are other systems that consider other factors, Sunset for example.

[Cid_Yama]

We did not get below 25 F this winter in North Texas. That's at least a full 10 F warmer than usual and has never happened before. Usually we have a couple weeks in January of low teens, even an occasional single digit, with highs never breaking above 20F.

Instead, we had a whole slew of days in the 70s with only a handlul of overnight lows breaking the freezing mark.

I'm not complaining for the loss of winter. It's this coming summer I'm dreading.

[Lore]

It's interesting in all the media reports the anecdotal observations of old timers witnessing the growth of plants much farther North then they have seen in their lifetimes.

The fact that this a quick, broad movement in temps and not localized adds to the concern.

[PrestonSturges]

We did not get below 25 F this winter in North Texas. That's at least a full 10 F warmer than usual and has never happened before. Usually we have a couple weeks in January of low teens, even an occasional single digit, with highs never breaking above 20F.
Instead, we had a whole slew of days in the 70s with only a handlul of overnight lows breaking the freezing mark.
I'm not complaining for the loss of winter. It's this coming summer I'm dreading.

It's like that all over the country even though I thought this was going to be a cold wet La Nina year kicked off by the Halloween snow storm at State College PA. And it seems like it's this way in the Southern Hemisphere as well, which has been roasting.

So WSJ runs an article denying AGW - I think they are getting desperate and frightened.

[Lore]

So WSJ runs an article denying AGW - I think they are getting desperate and frightened.

The Rupert Murdoch media spin machine attempting to tamp down what's becoming way to obvious for the average person to ignore. You would have thought though they could have come up with a better script and more credible signatories.

[dohboi]

We tied for the latest first temp below 0 F this year in Minneapolis. And that was the only dip below 0. This is very strange for this area. We can have weeks were it gets below zero every night.

Forty two forecast for tomorrows high and high thirties thereafter. Major winter festivities are being canceled or postponed. Almost no snow on the ground...

[Pablo2079]

Tulips are popping up in Western Washington and last night I heard frogs croaking. I think this activity is about 4-6 weeks early.

[dohboi]

They closed the ice rinks in the parks around here in the middle of January. A few of them reopened when the temperatures dipped briefly into the sub-zero zone, but now we're well up above freezing every day. The norm for February is to see very few temps above freezing the entire month.

I walk most places I go, and usually it is snow piles and ice one has to watch out for this time of year here. This year it is puddles and mud, which I associate more with April than Feb.

We had a very warm spring a few years ago when I put in peas on the first of March, and most of them sprouted, though it took a while. I'm wondering if I can start planting even earlier this year.

[Tanada]

Gardeners have come to rely on USDA Hardiness Zone Maps to tell us what plants will survive locally. The USDA released updated Plant Hardiness Zone Maps for the United States in 2012. Plant zones are based on the average annual minimum temperature over a 30-year period, not the lowest temperature the thermometer has ever hit, but rather the average.

These are guides to help a gardener determine which plants will survive in their garden. These are not steadfast rules, but rather guides to supplement other garden factors like soil quality, sun exposure, moisture and sudden or prolonged temperature swings. These combined local variables affect how well plants do.

Microclimates are variations within a hardiness zone, even within the radius of a gardeners yard. Trust the knowledge gained of your property and your gardens. Hardiness Zone is goodstarting point as you read plant labels here at Watters Garden Center.

http://www.prescottenews.com/index.php/ ... s-zone-map

[careinke]

Figuring out the microclimates on your property, and planting them correctly, will make a HUGE difference in your productivity, and make your life a LOT easier.

[Outcast_Searcher]

On the one hand I am glad they finally updated it, on the other hand I am puzzled. Normally the map is a 30 year average going from for example 1961-1990 while this map is 1976-2005. I know certain parties refused to update the map to 1971-2000 when it was due to be updated but I kind of expected this one to be 1981-2010 not 1976-2005. Basically all they did was take the Arbor Day zone map of 2006 and make it official. http://www.arborday.org/media/map_change.cfm

My zone has also shifted from 5 to 6, so less harsh winter temps.

And with all the fun with polar vortices and such, we get extremes on both ends. Several recent winters with average temps some months so warm it was like we never had winter. And a couple of winters where we had record temperatures or snowfalls, twice (or more).

So the new zones are applicable -- except when they aren't. The bad winters killed a hell of a lot of my perennials which I had planted in 2012, based on the newer zones (which I had seen published in gardening books in places like Home Depot).

[Tanada]

Arborday Foundation has now updated their map from 2006 to 2015 for those interested in additional changes to the base climate. For comparison ease I am posting both the 2006 and 2015 updates, there are some subtle changes over the last 9 years between maps.

[Tanada]

2006 zones.png

2015 Zones.png

[Newfie]

Thanks Tanada,

Good info.