I hope to put the finishing touches on garden clean-up around here this week as soon as it stops raining. (No, I’m not done yet. Yes, I know it’s nearly November.) While I wait for this autumn deluge to end, I am already thinking of spring and pondering what new varieties to try, and as I page through the early seed catalogs, I am torn between zones. To understand what I mean, take the following test.

Open the browser of your choice and enter your zip code in the “Zip Code” field on each of the following two websites:



The first website is the National Gardening Association website while the second belongs to the United States Department of Agriculture (USDA). I just did that very thing using my Careywood zip code of ‘83809’ and guess what? The National Gardening Association and the USDA do not agree on the cold hardiness zone for Careywood!

The National Gardening Association still lists my cold hardiness zone as 5b which is any area where the annual average winter low temperature doesn’t fall below -15 degrees F. This is the same cold hardiness zone that Careywood (and Bayview and Athol) have been associated with for as long as I’ve lived in Idaho (20+ years).

However, the USDA has decided this year that life in Careywood and the surrounding environs is a lot warmer than they’ve been telling us for the past umpteen years. Now when you enter ‘83809’ into the zip code field on the USDA website, it pops up 6a with annual average winter low temperatures that don’t fall below -10 degrees F. Yikes! Holy global climate change, Batman!

Most of you are probably asking yourselves, so what? When the temperature is below zero (which is just plain too darn cold, thank you very much!), what difference will 5 degrees make one way or the other? Well, the answer is probably not much to humans, but, with plants that 5 degrees can be the difference between one that survives the winter and one that doesn’t.

The USDA cold hardiness zone map was first established in 1960 as a way for gardeners to match their climate with the climate in which a plant is known to grow well. I guess the USDA didn’t think that we gardeners north of the 25th parallel could figure out by ourselves that we shouldn’t try to grow bananas.

Now, mind you, I’m not saying that the cold hardiness zone map has not been useful as a general guide, but with the recent reassignment of our area from one zone to another, I’m beginning to wonder how seriously we really need to take this. I don’t know about you, but it hasn’t seemed all that much warmer at my house in recent years despite a relatively mild winter this year. I’m probably not going to run right out and start replacing my peonies (hardy to Zone 2!) with blue mist spirea (hardy to Zone 6).

On the other hand, I’ve been known to try a Zone 6 plant now and then when I had a protected spot for it and the ability to provide a little additional winter protection. A south or southwest facing wall or a spot where two buildings come together to form a cozy nook protected from winds out of the northwest can provide a Zone 6 micro-climate for the adventurous gardener.

Sure, I sometimes lose that Zone 6 darling to extreme weather conditions, but I’m philosophical about my losses. Life is about risk, and gardeners and farmers understand that as well as anyone. Every year we put seed and plants in the ground then water, weed, fertilize and battle the critters for the harvest. Some years we’re more successful than others, but we don’t stop trying just because of a crop or plant failure. In the end, I think it’s the persistence of the gardener that determines success more than the hardiness zone assigned to us by a bureaucrat in Washington, D.C.

“We come from the earth, we return to the earth, and, in between, we garden.”