One of the most important concepts to understand as a new gardener is what “hardiness zone” or simply “zone” you live in. Knowing what zone you live in will determine what plants will thrive in your garden, as well as roughly when you should be planting those delicious veggies!
So, what is a hardiness zone?
Wikipedia defines a hardiness zone as follows:
“A geographic area defined to encompass a certain range of climatic conditions relevant to plant growth and survival.
Developed by the United States Department of Agriculture as a rough guide for landscaping and gardening, defines 13 zones by annual extreme minimum temperature.”
The 13 zones mentioned are the average annual extreme minimum temperature broken into 10 degree (farenheit) groups. Zone 1’s minimum temperature range, for example, is -60F to -50F.
These zones have also broken down further into a’s and b’s for each zone. Meaning that 10 degree range is now split into two 5 degree ranges.
The area of Virginia I live in is located in zone 7b. Our minimum temperature falls in the 5F to 10F range.
Why is this useful?
Knowing what zone you live in will help you determine quite a few things.
Frost dates – almanac.com will tell you when the average first and last frost dates are for your region. This will help you figure out when you can plant, and when you should have your last crop out of the ground. Keep in mind, though, that these are AVERAGES. To be much more safe, it is okay to wait a week or two past the last frost date to start planting.
What you can grow – some plants, such as citrus trees will not do well in a colder climate. Others, such as lettuce and kale will not do well in a hotter climate. I use a planting schedule to help me figure out what I can plant, and when I should plant it. This will become second nature to you as you grow in skill and experience, but when you’re just starting out I recommend doing all the research you can!
There can be a few work arounds for those that live in cooler zones.
Plants such as herbs and citrus trees (which will die after the first hard frost) can be planted in containers and brought inside during the colder months.
You can create “mini zones” around your garden by planting near walls, or even fences, that will reflect some of the heat given off by the sun back onto your plants.