Augusta, ME Frost Dates
Average frost dates, USDA hardiness zone, and growing season length for Augusta, Maine.
Gardening in Augusta
Maine's capital sits on the Kennebec River, where the state's agricultural heritage connects to its community food growing movement.
Zone 5a with 143 frost-free days. The Kennebec Valley provides fertile bottomland. Central Maine's climate is honest — cold winters, beautiful summers, and a compact growing season.
Augusta's Viles Arboretum demonstrates Maine's horticultural possibilities. The capitol city's community gardens connect state government workers to local food production.
What This Means for Augusta Gardeners
The average last spring frost in Augusta is around May 8, and the average first fall frost arrives around September 28. That gives you approximately 143 frost-free days to work with.
At 143 days, you're working with a compressed but productive window. Choose varieties by their days-to-maturity number — anything under 75 days is safe, 75-90 requires indoor starting, and 90+ is a calculated risk. The tradeoff: your cool, moderate summers are excellent for crops that heat-zone gardeners struggle with. Your lettuce doesn't bolt in June. Your peas produce for weeks longer. Cool-season crops are your superpower.
These dates are based on NOAA 30-year Climate Normal data for the Augusta area. Your actual frost dates could shift 2-3 weeks in either direction in any given year. Learn more about our data sources.
What to Grow in Augusta
With 143 frost-free days, Augusta gardeners need to plan strategically — start warm-season crops indoors and choose short-season varieties. Cool-season crops are your strength, thriving in the moderate temperatures that define your growing window. Recommended starting points: kale, lettuce, peas, carrots, potatoes, radishes, garlic, and short-season tomatoes.
See the full Maine planting guide for all 40 plants: Maine Planting Calendar. Or enter your zip code for exact planting dates personalized to Augusta.
More About Zone 5A
Augusta is in USDA Hardiness Zone 5A, which means average annual extreme minimum temperatures between -20°F to -15°F. View the full Zone 5A planting guide.
See the complete planting calendar for Maine: Maine Planting Calendar.
Other Cities in Maine
Frequently Asked Questions
These dates are based on NOAA's 30-year Climate Normal data for the Augusta area. They represent historical averages, not predictions. In any given year, the actual last frost could be 2-3 weeks earlier or later. Microclimates within Augusta (urban heat islands, hilltops, low-lying valleys) can also shift your local frost dates by a week or more.
Start everything possible indoors — your 143-day season doesn't leave room for a slow start. Direct sow only the fastest, hardiest crops (radishes, lettuce, peas) 3-4 weeks before last frost (May 8). Choose short-season varieties for warm crops. Enter your zip code for exact dates.