Plant Hardiness Zone:

The Plant Hardiness zone is a guide to let you know which plants will grow and survive where you live. Hardiness zones show the coldest average temperatures for each region. If a plant is referred to Zone 6 – we know that it will withstand a winter in that area.

So why does it matter if we are growing in a greenhouse? These charts will let us know if we will need to add additional heating for the plants that we are growing, depending on the area that we are in. The charts let us know the average coldest temperature that that plant can withstand. So we need to make sure that the temperatures do not reach that temperature.

Plant Zones are not the only thing to watch for:

These Plant Hardiness zones are a great place to start, but temperature isn't the only thing that plants need to survive.

We still have to think about soil, water, daytime temperatures, day length and sun, wind, humidity and heat.

That is the beauty of a greenhouse we can grow any type of plants that we would like, because all of these other climate variables can be controlled in a greenhouse!

Take a look at the Hardiness Zone Charts:

This chart shows the USDA zones and the average coldest temperature for each of those zones in both Celsius and Fahrenheit:

USDA Zone Chart:

From Plant Hardiness Zone to Home Page

USDA Zone System:
CelsiusZoneFahrenheit
Below -461Below -50
-40 to -462-40 to -50
-34 to -403-30 to -40
-29 to -344-20 to -30
-23 to -295-10 to -20
-18 to -2360 to -10
-12 to -1870 to +10
-7 to -12810 to 20
-7 to 0920 to 32