By Emily How, Horticulture agent

NDSU Extension – Ward County

Did you know you can explore Google’s top searches of the year? Everything from the most trending search (the election), the top trending recipe (Olympic Chocolate Muffins), and the most searched pickle recipe (dill pickle bread) is available on Google. You can even look at specific state data.

According to Google Trends, the most asked gardening question for North Dakota was, “What is my hardiness zone?”

Hardiness zones are a system that categorizes regions. The maps are based on the average high and the average low of an area and then grouped into zones. Gardeners and growers use hardiness zones to determine which plants will thrive in a specific location. The U.S. Department of Agriculture (USDA) creates and maintains the hardiness zone map.

These maps can be incredibly helpful when planning a perennial garden, especially if you are new to an area or new to gardening. For example, my family in Texas grows lantana as a perennial. In North Dakota, lantana is grown as an annual because it is not hardy enough to withstand the winter. The opposite is also true, delphiniums are grown as a perennial in North Dakota, but in Texas they get too hot and do not grow as well.

Hardiness zones are a good starting point to determine a plant’s growing suitability in a region, but other considerations should also be taken. For example, are you planting in a raised bed or in a container? Does the area you are planting get a lot of snow cover? Are you planting in an area surrounded by concrete?

These things can impact how well the plant performs in that area. If you are planting in a container, it will not receive the same insulation from the soil as plants grown in the ground. Snow also provides insulation and can keep a plant warmer through the winter. Concrete also warms an area and can cause the plants to receive more heat during the summer.

You could also be in something called a climate microzone or a microclimate. These can be caused due to elevation, nearby water sources, or man-made features. Urban areas tend to be warmer than rural areas, lower elevations tend to be colder and geographical features like water can impact the temperature in a region.

If you are a cautious gardener, selecting plants with a lower zone than your area can be a safe way to make sure the plant survives through a North Dakota winter. I live in zone 4, so with high-value plants I always like to get plant varieties that are hardy to zone 2 or 3.

Sometimes I take a bit of a gamble, like purchasing a weigela that is hardy to zone 5 for the color. It is currently placed in a sheltered corner of my house that gets a significant amount of snow. I just need to wait and see if it survived the winter or if my gamble paid off.

What was your garden question this year? Email me and let me know!

For more information about gardening, contact your local NDSU Extension agent. Find the Extension office for your county at ndsu.ag/countyoffice.    

NDSU Agriculture Communication – Jan. 10, 2025

Source: Emily How, 701-857-6444, emily.how@ndsu.edu

Editor: Kelli Anderson, 701-231-6136, kelli.c.anderson@ndsu.edu