Portland, Maine planting calendar and frost dates

Frost dates in Portland

NOAA U.S. Climate Normals 1991-2020 for Portland International Jetport, 2.4 miles WSW of the city center. Low-lying and rural spots often frost later in spring and earlier in fall than airports and city centers.

What to plant each month in Portland

1. January

   Start indoors: onions

2. February

   Start indoors: broccoli, cabbages, cauliflower, collard greens, kale, leeks, onions, oregano, parsley, petunias, ranunculus, rosemary, snapdragons

3. March

   Start indoors: black-eyed susans, broccoli, cabbages, cauliflower, celery, chives, cilantro, collard greens, eggplants, ginger, leeks, lettuce, marigolds, nasturtiums, oregano, parsley, peppers, petunias, ranunculus, rosemary, sage, snapdragons, spinach, swiss chard

   Plant or sow outdoors: beets, black-eyed susans, blackberries, blueberries, broccoli, cauliflower, chives, cilantro, collard greens, figs, garlic, gladioli, grapes, grass seed, hollyhocks, kale, leeks, onions, peas, poppies, radishes, ranunculus, raspberries, rhubarb, roses, spinach, strawberries, swiss chard, turnips, wildflowers

4. April

   Start indoors: basil, cantaloupes, celery, eggplants, peppers, ranunculus, tomatoes, watermelons

   Plant or sow outdoors: beets, black-eyed susans, blackberries, broccoli, cabbages, carrots, cauliflower, chives, cilantro, collard greens, dahlias, dill, figs, garden mums, gladioli, grapes, lavenders, leeks, lettuce, lilies, marigolds, mints, nasturtiums, onions, oregano, parsley, petunias, radishes, ranunculus, rosemary, roses, sage, snapdragons, spinach, swiss chard, thyme, turnips

5. May

   Start indoors: cantaloupes, cosmos, cucumbers, okra, pumpkins, watermelons, winter squash, zucchini

   Plant or sow outdoors: asparagus, chives, cilantro, dahlias, dill, garden mums, ginger, gladioli, grapes, green onions, kentucky bluegrass, lavenders, lettuce, lilies, marigolds, mints, nasturtiums, oregano, parsley, perennial ryegrass, petunias, potatoes, ranunculus, rosemary, sage, spinach, st. augustinegrass, sunflowers, sweet corn, sweet peas, swiss chard, tall fescue, thyme

6. June

   Start indoors: zinnias

   Plant or sow outdoors: asparagus, basil, bermudagrass, cantaloupes, celery, centipedegrass, cosmos, cucumbers, eggplants, green beans, green onions, okra, peanuts, peppers, pumpkins, st. augustinegrass, sweet potatoes, tomatoes, watermelons, winter squash, zoysiagrass, zucchini

7. July

   Plant or sow outdoors: bermudagrass, celery, centipedegrass, cosmos, green onions, okra, peanuts, st. augustinegrass, zinnias, zoysiagrass

   Plant for fall: bearded irises, broccoli, brussels sprouts, carrots, collard greens, lettuce, peas, snapdragons, swiss chard

8. August

   Plant for fall: azaleas, bearded irises, beets, broccoli, cabbages, carrots, cauliflower, clematis, collard greens, coneflowers, daylilies, hostas, hydrangeas, kale, lettuce, peas, radishes, roses, saffron, snapdragons, spinach, swiss chard, turnips

9. September

   Plant for fall: azaleas, bearded irises, cabbages, cauliflower, clematis, coneflowers, crocuses, daffodils, daylilies, grass seed, hostas, hyacinths, hydrangeas, kale, lilies, ornamental alliums, peonies, radishes, roses, saffron, spinach, tulips

10. October

    Plant for fall: crocuses, daffodils, garlic, hyacinths, lilies, ornamental alliums, peonies, tulips

Frost dates and zones by ZIP code in Portland

All 6 of Portland's main ZIP codes take their frost dates from Portland International Jetport, so the dates on this page apply across the city. Every one of them is in zone 6a.

Planting dates for popular crops in Portland

Nearby cities

• Haverhill, MA zone 6a, last frost May 1
• Manchester, NH zone 6a, last frost Apr 30
• Lawrence, MA zone 6b, last frost Apr 13
• Peabody, MA zone 6b, last frost May 3
• Lynn, MA zone 6b, last frost Apr 4
• Lowell, MA zone 6b, last frost Apr 30