Have you ever had the disappointment of planting your favorite vegetable but found it just didn’t grow?
This may be why: It may have failed because the vegetable was not suited to your Hardiness Zone or because you were simply not paying enough attention to your local frost dates. Experienced gardeners use these guides yearly. They are simple guides that help you to select the type of plants that will grow well in your area and when to plant them. This gives you a better chance at a successful garden.
Let’s take a look at the different aspects of Hardiness Zones and Frost Dates to get a better understanding of what they mean and how they can help us.
The Hardiness Zone map should be used as a starting point. You need to look at your area and your own yard, and consider the weather and conditions in your region before planting.
Zones tell us which plants can survive in our region’s climate during regular gardening season, as well as which shrubs and trees can survive outdoors year-round in our area. Usually on the back of seed packets you will find a map showing where the plant will do best. You can find the same or similar map on plant tags.
Canada and the United States both have their own divisions of Hardiness Zones. Canada has nine. They range from 0 to 8, with 0 being the harshest. Within each zone there is another division, A and B, with A being harsher. Wind patterns, rainfall, snow cover, average number of frost-free days and temperatures (minimum and maximum) are used to create the zone map.
The USDA Hardiness Zone Map is only one of several maps to help gardeners, but this is the map most gardeners turn to for advice and guidance. This map divides North America into 11 zones, and each zone varies within 10 degrees either warmer or colder than the other zones.
These dates usually reference the first and last day’s frost of a year. For example, the first day would occur in autumn and the last day would happen in early spring of the following year.
By using these dates as a guideline, you will be able to plan when you can start planting an outside garden, or preparing your indoor one. It is helpful because you wouldn’t want to plant a vegetable like tomatoes in August if the frost date is in September. They wouldn’t have time to grow and be harvested.
The amount of time between the two frost dates determines how long your growing season will be. You can then plan what vegetables will grow during the time you have. You will need to plant something that will mature during the time you have, or you can use cold frames. Plants will also stop producing if you have several days in a row of continuous temperatures.