By Niki Morock, Meteorologist
If it seems like we’ve had an unusual winter so far, it’s true. According to the North Carolina Climate Office’s blog post, “A Cold, Snowy January Brings Drought Relief,” we just survived “the 11th- coolest January on record dating back to 1895, and the coldest since 1988.” I speak for most of my friends when I say that I’m happy that frigid month is over.
Normal high temperatures for this time of year in the Triangle are in the low-to-mid 50s: normal lows are in the lower 30s. We’re creeping back toward normal-to-above normal as a trend, and it looks like the worst of the unusual cold may be over. However, it is still early February, so there will still be cold days, and our potential for winter weather doesn’t really end until mid-to-late March. My point is that it looks like the trend will be for the normal or warmer-than-normal days to outnumber the unusually cold days from this point forward as we move toward spring.
As I happily look ahead to warming temperatures, I have a small garden plot on my mind.
If you’re a regular reader of this blog, you know I bought my first house last fall. One of the many reasons I fell in love with the little ranch was the fact that it had a garden in the yard, producing tomatoes, peppers, and mint. What an exciting idea – an opportunity to grow my own produce the way my grandparents did when I was growing up! Every time I look at the plot, it reminds me of my Papop. Despite those happy memories, I admit that I have very little idea of what I’m doing out there. I have a lot to learn.
My helpful neighbor is an avid gardener, and she loaned me her favorite book on the subject. As I’m reading, it has me thinking about the weather and our climate – of course! This week, my goal is to decide what I want to plant. Part of me would like to plant some unusual seeds so that my garden isn’t exactly like everyone else’s. Unfortunately, every interesting plant I look up doesn’t grow in our zone. No wonder no one around here grows them. Yes, I’m learning about plant hardiness zones, and wondering how many people know that they have changed within the last decade and will probably change again in the next one.
Your zone may be higher than you think.
An article on Rodale’s Organic Life website explains that the United States Department of Agriculture (USDA) updated its Hardiness Zone Map in 2012. The map is based on the 30-year average of the coldest days of the year for each area. Those averages are calculated and tracked by the National Oceanic and Atmospheric Administration (NOAA) and are the same climatology that meteorologists use when talking about “normal” temperatures and precipitation. Our current 30-year period is 1981-2010, so that is what the new USDA Plant Hardiness Zone Map is based upon.
According to the USDA map, my neighborhood in eastern Wake County is in zone 7b, but very close to 8a. Plants that do well in either zone should be fine in my garden.
The Arbor Day Foundation has taken zone mapping a step further and created one just for trees – their primary focus. Unlike most garden plants, trees will be around for decades, so the future climate should be considered when deciding what kind of tree will thrive in your area. According to the Arbor Day map, most of our area is solidly in zone eight.
Larger operations need to plan for future plant hardiness zones.
Reading about hardiness zones has reminded me of a local American Meteorological Society chapter meeting at the State Climate Office two years ago. Then-State Climatologist Ryan Boyles introduced us to the PINEMAP Decision Support System – a tool for forestry professionals and tree farmers to use in determining what trees to plant both now and in future decades. Large scale operations should be thinking well beyond the next ten years if they want to continue to produce strong results.
The tool is specifically geared toward planted pine forest owners, and provides some interesting predictions based on current data and climate research. Its interactive map can let you see how the plant zones may change in coming decades if the climate changes according to the models’ predictions. It is truly meant to help tree farmers adapt and thrive, which is a fantastic use of climate prediction models.
Personally, I’m not planting any more pine trees in my yard because I have enough to supply pine straw to a small town for years. Still, I found the PINEMAP DSS fascinating. For my garden though, I’ll look at the current forecast trends, the USDA Plant Hardiness Zone Map, and other local information to decide what to plant in my little garden. Who knows? Maybe I will find something unique to add to the tomatoes, peppers, and mint that the previous owners produced last year. I am open to suggestions.