The city of Lansing, Michigan, is situated within USDA Plant Hardiness Zone 6a, according to the most current map data released by the United States Department of Agriculture (USDA) in 2023. This designation indicates which perennial plants are most likely to survive the area’s coldest winter temperatures. Lansing was previously classified as the slightly colder Zone 5b. This shift reflects a broader trend seen across the country.
Defining the Plant Hardiness Zone System
The USDA Plant Hardiness Zone Map is the standard reference tool for determining where specific plants can successfully grow year-round. It is based entirely on the average annual minimum winter temperature recorded over a 30-year period. This metric helps predict a plant’s ability to withstand winter lows.
The map is divided into 13 main zones, with each full zone representing a 10-degree Fahrenheit range of minimum temperatures. To provide greater precision, each zone is split into two half-zones, labeled ‘a’ and ‘b’. These half-zones, such as 6a and 6b, each represent a narrower 5-degree Fahrenheit temperature difference.
Lansing’s Specific Zone Designation and Climate Data
Lansing, Michigan, is officially categorized as Zone 6a based on the latest 1991–2020 climate data. This designation indicates that the average annual coldest temperature in the region falls within the range of -10°F to -5°F (-23.3°C to -20.6°C). The shift from the older Zone 5b, which had a minimum range of -15°F to -10°F, suggests a moderation in the area’s extreme winter cold.
This change reflects recent climate trends and improved data resolution, accounting for factors like the urban heat island effect. While the surrounding region may still contain pockets of the colder Zone 5b, the Lansing metro area, including East Lansing, is largely identified as Zone 6a.
Applying Zone Information for Successful Gardening
Gardeners in the Lansing area should use their Zone 6a designation as a primary guide when selecting perennial plants, trees, and shrubs. The general rule is to choose plants labeled as hardy to Zone 6 or a colder zone, such as Zone 5 or 4. Selecting a plant rated for a warmer zone, like Zone 7, means it is likely to be damaged or killed during a typical Lansing winter.
The hardiness zone map is a tool for perennial survival, but it does not account for all local growing factors. Gardeners must also consider specific microclimates, which are influenced by wind exposure, soil drainage, and proximity to buildings. Furthermore, the map does not provide information about first and last frost dates, which determine the length of the growing season for annual crops.