Tag Archives: Plant hardiness zones

Plant Hardiness Zones Racing Toward the Poles

“Sweetheart, what hardiness zone are we in?” It’s getting late in the fall season, and Barbara is reading up on whether or not to bring her thyme plants indoors.

What plant hardiness zone are we in?

What hardiness zone are we in?

Like all growers, we care about plant hardiness zones. They guide us with regard to planting times and suitable plant varieties. They tell nurseries when to ship saplings to us, and when we ought to plant them. Just now, they’re going to settle for Barbara whether or not to dig up her thyme. But at the moment, I somehow can’t remember.

“I think we’re in seven. Or maybe six. Let me check.”

There are eight plant hardiness zones in the United States, as determined by the USDA. Zone 3 is a thin strip up along the Canadian border. Only the hardiest plants will survive the winter up there. Zone 10 is basically South Florida, where winter is always balmy.

It turns out I had a good reason for my confusion about our zone at Good Hand Farm. When we started farming here, almost all of New Jersey was Zone 6. Fifteen years later, it’s basically all Zone 7. The plant hardiness zone has moved about 200 miles north in sixteen years. That’s about twelve miles per year, around here.

But it’s happening just about everywhere. In 1990, virtually all of Kentucky was Zone 6. By 2006, the whole state was zone 7. In the Upper Midwest, the border between Zones 4 and 5 ran through Sioux City, Iowa. Now it runs through Minneapolis, more than 200 miles north. Virtually every state has experienced one zone change in less than twenty years. At this pace, in one century, New Jersey would be about four hardiness zones hotter, like Miami, or maybe South Texas.

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Notice the black zone (Zone 3): Almost all gone since 1990.

Repeat that: New Jersey would be like South Texas in one century.

So, how do you grow trees when you’re changing the climate this rapidly? Trees can live for hundreds of years. Two sugar maples out our front door are nearly two centuries old. What happens to them now, as every couple decades ushers in a whole new climatic zone? And what happens to our forests, brimming with cold-weather species, but now subject to increasing heat every decade?

We are performing a massive, uncontrolled experiment upon ourselves, and upon all the creatures who share our communities. When are we going to grasp how reckless it is to radically alter climate conditions within a single human generation?

Climate change is real. It’s high time our politicians own up to the fact, and begin to work on solutions. Why not contact your Congressional representatives, and ask them where they stand? Otherwise, you might have New Jersey feeling like South Texas or Miami. And if so, those places would feel like something straight out of your worst nightmares.

The time to do something is now. This world belongs to God, and we’ll surely have to account to him for what we’ve done to it — or for our silence while others did so.

Contact your Congressional Representatives.