Here's the url: www.planthardiness.ars.usda.gov

The press release is at http://www.ars.usda.gov/is/pr/2012/120125.htm

Enjoy!

Kevin

The new map definitely puts me smack in the middle of zone 6a, but I always knew my town was close to the borderline of 5/6. No doubt the center of town, where it is more densely settled and there is a "heat island" affect, is zone 6a. My property is located at the outskirts of town, across from farmland and exposed to strong northwest and southwest winds with a surrounding landscape that creates a wind tunnel effect during the winter. It just feels colder here.

I would plant only fully zone 5 hardy plants in my gardens, because of their exposure, with perhaps more tender plants close to the house foundation.

I have been using zone 6a for some years now, but it's nice to be validated by the experts. ;)

Thanks for the link!

We had an article in our local paper today about the new USDA map (which puts most of Ohio in zone 6). They interviewed a manager at our largest (and best) nursery in central Ohio (which was previously placed on the border between zones 5 and 6 and is now all zone 6). He said he was continuing to tell customers that we are in zone 5, because we're still going to have extreme winters or severe storms from time to time.

That's not the point of climate zones, which are determined by the average winter low temperature. If zone 6 gardeners see an wintertime low on average of -5F but are faced every decade or so by a drop to -20F, they are still in zone 6, not the border between zones 4 and 5. A severe cold snap might damage or kill susceptible plants (depending on site, drainage and snow cover) but it doesn't make sense to garden with these extremes in mind.

Of course you could play it safe and only use plants that are semi-guaranteed to be rock-hardy in your area, but you'll miss out on a lot of great things. If (for example in my area) you get years of enjoyment from a Nandina or crepe myrtle but it eventually succumbs to a hard winter, you're still ahead of the game.

The nursery I would think he is telling the customer "do not get angry with me if the plant dies if you buy a zone 6 and we have a zone 5 winter". Who are they going to blame. HIM!!! LOL

How many times do you see people say my plant is not performing and they planted it in the shade and it should be a sun plant or vise versa.

There are plants I buy and know they are iffy but I know that going in I do not plant it as part of the bones of the garden setting or a plant that I expect to depend on having long term. If it lives as you said good, if it dies and I expect it might it is still good. It is just how you look at it with knowledge.

Not only can a whole garden be in a microclimate (mine is because it is surrounded by Rock Creek Park--the largest urban green space in the country, leaving me a half zone cooler than neighbors only a mile away), within gardens there are often mini microclimates--nanoclimates?--that low spot where frost pools first or the warm spot in front of a white south-facing wall.

Given that suing people is America's second favorite indoor sport, nothing is going to stop people from wanting to blame someone else for their failure with a plant.

KimKa, who pushes the sun requirement for plants all the time rather than the hardiness zone

Ripe for this is the Sunset national gardening guide. I have the first edition, which may be great for western states (especially California, which has been broken down into a host of numbered zones), but was far less satisfactory when it came to the rest of the country. My area for example was lumped in with eastern Iowa (which historically has been rated a full zone colder by the USDA), and the accompanying article suggested that when it came to perennials I was limited to choosing hardy prairie plants. Anyone taking this as gospel would be severely (and unnecessarily) restricted in what they grew.

Existence of the new national zone map doesn't mean it's a great idea to fill your garden with borderline plants, but as noted, some experimentation is fun and rewarding.

KimKa, who pushes the sun requirement for plants all the time rather than the hardiness zone

A gardener after my own heart. For those of us in tight urban settings it is sun, not temperature that is at a premium.

We need a separate thread for those of us pushing the envelope re sun 'requirement'. I would love to know what sun loving plants others grow successfully in (much) less than 'full sun'.

Sandy

Full sun can mean about 5 hours of sun a day, not necessarily full hot all day sun.

For me and my property where sun is in short supply many of my perennials that are listed as FULL SUN (i.e. greater than or equal to 6 hours) generally do fine with 4 hours of morning sun (say 9 till 1).