Maine Planting Zones

In the upper most Northeastern state, Maine, planting zones are limited to the lower range of the USDA growing chart. Maine’s climate is humid continental, which means the state generally sees humid and pleasant, warm summers that for the most part are not extremely hot for any length of time. The entire state sees very snowy, cold winters, with the most snowfall occurring between the western and northern parts of the state. Maine’s coastal regions are somewhat moderated by the Atlantic Ocean, which results in a bit cooler summers and milder winters. Mid-summer daytime highs average between 75 – 80 degrees and nighttime lows dip just to the 50s. Winter temperatures range from below 0 degrees in the far north to highs around 30 degrees on the southern coast. 

U.S. planting zones were developed to help guide gardeners to know when to plant and what plants will survive and thrive their area. Maine planting zones range from 3b to 5b, with just a few very small areas in the southern region of the state reaching up to 6a. It is quick and easy to determine your growing zone with Gilmour’s Interactive Planting Zone Map. The northeastern parts of the state are the lowest zone, and have the coldest winters. Maine planting zone awareness can be used as a guide for choosing plants that have the best chance of survival. Selecting plants that are rated for the zone you are in or below is a good rule of thumb. Plants rated much higher than a specific zone would likely have a very hard time surviving harsh winter months in Maine growing zones. Planting zones help determine when plants should be planted based on first and last frost dates. 

Maine enjoys a wide variety of blooms and foliage that all do well in the area. Coreopsis, echinacea (coneflower), lupine, iris, hyacinth and daffodils all thrive in these zones. Milkweed, arrowwood, nannyberry, the Virginia rose and northern bush honeysuckle are all native to Maine and are loved by gardeners for their hardiness and abundance. When planning a vegetable garden, knowing the Maine growing zones is important as well so you know when to put tender veggies in the ground. Vegetables that thrive in the state can include beets, cauliflower, lettuce, carrots and radish.