Learn About Hardiness Zones

In this section, we’ll learn how to buy plants that will live in your climate by using hardiness zones.  This is very important.  Many new gardeners make the mistake of buying plants that will not survive in their environment.  Hardiness zones help us make the right choice.

Know Your Hardiness Zone!

The US Department of Agriculture (USDA) has divided the country up into zones depending on the local climate.  Each zone has a number.  Lower numbers signify colder climates.  I live in a part of Massachusetts that is designated as zone 6.  Some zones are also divided further into “a” and “b”.  In order to be a smart plant shopper you definitely need to know your USDA Hardiness zone.  Since all plants will not grow in all climates, nurseries will label plants by referring to their “hardiness zone(s)”.

To know your zone, you can check several websites.  My favorite is the National Arboretum site:


Once you know your zone, you’ll be better equipped to buy plants.

Plants should be labeled with a range of zones the plant can live in (for example Zones 3-7).  But mostly plants are only labeled with the coldest zone they can survive in.  So if your plant tag only says “Zone 6”.  That means that the coldest climate this plant can live in is zone 6.

In order to sell more plants, sometimes nurseries will stretch the truth about plants claiming they’ll live in colder climates where they may actually only marginally survive.  For this reason, I always buy plants labeled one zone colder than my zone.  So for me, I buy plants labeled zone 5 or lower even though I live in zone 6.  There are always reasons to make exceptions, but buying one zone colder than yours is always a safe bet.


Here’s a quick summary of what we learned in this section:

  • You should know your USDA Hardiness zone.
  • You can find your zone at http://www.usna.usda.gov/Hardzone/
  • The zone listed on a nursery tag is the coldest zone where the plant can survive
  • You can play it safe by buying plants one zone more hardy (one number lower) than the zone you live in.

Next: Learn to more about buying the right plants in HOW to READ NURSERY TAGS