The story below is an excerpt from our November/December 2017 issue. For the rest of this story and more like it subscribe today, log in to read our digital edition or download our FREE iOS app. Thank you!
I cannot endure to waste anything so precious as autumnal sunshine by staying in the house. —Nathaniel Hawthorne
Ginny Neil
When I was in kindergarten, my family moved to the foothills of the Smoky Mountains. The stone patio off of the kitchen in our new house faced south. It didn’t take me long to discover that I could nap there in comfort on most sunny fall days. Even if the wind was blowing, the cement floor of that rock-lined patio acted as a heat sink creating a cocoon of warmth for my cat and me. I didn’t know it at the time, but that was my first experience with microclimates.
My mama also recognized the value of that little microclimate. She planted her herb garden in the yard at the base of the same wall. There, the southern exposure and the heat-retaining warmth of rocks allowed her to grow some herbs like rosemary that wouldn’t have made it through the snowy Tennessee winters.
I grew up and lost interest in curling up with the cat. Then I moved to the mountains of Virginia, married My Own Farmer, and started an herb garden. According to the USDA Hardiness Zone Map, my farm is barely in zone five, and many winters, when the wind howls off of the mountains, it is squarely in zone four. I longed to grow rosemary, but like Mama, found the climate too cold for it to survive. That’s when I re-discovered the lesson of the patio. My house has a stone patio that faces southwest, and if I plant rosemary in the sheltered corner, sometimes it lives a couple of years before a really brutal winter takes it out.
Microclimates are a great way to play with your growing season. Basically they are small areas around your property that are either a bit cooler or warmer than your designated hardiness zone. This variation in normal temperature from what’s the average around your yard is due to either sheltering or warming structures. Sometimes a small body of water, like an in-ground pond or pool, can also create microclimates since water warms and cools slower than air.
One great way to locate your microclimates is to let your pets find them for you. If you want to grow a plant that needs one zone warmer to survive the frost, follow your cat. Any place that a cat curls in the sun is a good candidate for a plant that prefers a climate slightly warmer than yours.
On the other hand, if you want to grow plants that prefer a cooler climate than your summers allow, then check where your dog hangs out in the heat of the day. Those spots are great places for plants that wilt easily.
You can also create microclimates. If you live in the south, plant cool-loving plants on the east-facing side of your house. Morning sun is far less punishing than afternoon rays. In northern zones, put a large boulder in your garden and plant heat-loving plants on the southwest side. The boulder will absorb heat during the day and release it at night, allowing your plants to survive when winter blows through.
The discovery of my own microclimates has resurrected a childhood pleasure. If you happen to visit on a nippy November day, and I don’t open the door to your knock, just mosey on around to the back of the house. You’ll find me sprawled on the warm rocks of the patio next to my rosemary plant and my dog, Luke. Feel free to pull up a cat and join me for an afternoon nap.