Cold Hardiness

Cold hardiness is relative to moisture, wind, and temperatures fluctuations so many gardeners use zone maps as a general rule of thumb or a simple guideline. Understanding the new heat zone maps can be confusing for homeowners, so many of us use thecold hardiness zone map and pay careful attention to how different areas of our yards tend to be more protected from the elements. Protection is the key to understanding the hardiness of plants.

Exposure to the elements can reduce the hardiness of a plant by a full zone. Winter winds and cold/warm fluctuations endanger plants more than prolonged cold temperatures so a wise gardener will take note of these areas and use plants a zone colder and protect soil and plants with mulch. In a protected area next to a foundation on a south side, then perhaps you can use plants a zone warmer than you normally would. In any yard it is possible to have areas that would be in three different zones. This is true in my yard where I have zone 3 plants out in the windy area, but next to the covered patio on the south side of the house I have many zone 5 plants. Over all planting areas, I layer mulch for winter to ensure even soil temperatures and moisture retention.