Fall · September 8, 2026

Portland, Maine

Acadian Forest & Atlantic Coast·Hardiness zone 6a

Now

25°C · Clear

Today

26° / 14°

Soil 6 cm

19°C

First frost

~56 days (Nov 3)

Gardening in Portland

AI field guide · refreshed weekly

Portland Gardening: Early September – Harvest, Plant Fall Crops, Prepare for Frost

You're in zone 6a with 56 days until your average first frost (Nov 3). Soil at 19°C (66°F) is still warm enough for direct seeding cool-season crops. Spring frost averaged Apr 24, so you've had 137 frost-free days already—use this window to establish fall vegetables that need 50–70 days to mature before hard freeze.

Sow outdoors now

  • Spinach (Bloomsdale Long Standing, Space)

    Sow directly now; germinates in 7–10 days at 19°C soil temp. Harvest in 40–50 days before hard frost.

  • Arugula (Roquette)

    Direct seed; matures in 30–40 days. Tolerates light frosts, so you can succession-sow through mid-September.

  • Lettuce (Winter Density, Buttercrunch)

    Sow now for fall harvest; cold-hardy varieties will survive early frosts if mulched. Thin to 15 cm (6 in) spacing.

  • Radish (Cherry Belle, French Breakfast)

    Ready in 25–30 days; plant every 10 days through late September for continuous harvest.

  • Kale (Lacinato, Winterbor)

    Direct seed or transplant; improves in flavor after light frost. Matures in 50–65 days; plant by late September.

Start indoors now

  • Broccoli (Calabrese, Arcadia)

    Start indoors now for transplant in 4–5 weeks; needs 60–70 days to head. Set out by early October for November harvest.

  • Cabbage (Red Acre, Savoy)

    Start indoors; transplant in 4 weeks. Fall cabbage stores well and tolerates light frost once established.

  • Cauliflower (Snowball, Graffiti)

    Start indoors now; transplant in 4–5 weeks. Needs consistent moisture and 55–70 days to curd; target October planting.

Harvest now

  • Tomatoes (all varieties)

    Pick ripe fruit now; bring green tomatoes indoors to ripen or make salsa. Frost risk rises after Oct 1; pull plants by mid-October.

  • Peppers (sweet and hot)

    Harvest mature peppers; immature fruit can ripen indoors. Frost will kill plants, so clear beds by late September.

  • Beans (bush and pole)

    Pick regularly to encourage final flushes. First frost will end production; pull plants once frost threatens.

  • Summer squash and zucchini

    Harvest daily; plants decline as nights cool. Remove plants once production slows or frost arrives.

Tasks this week

  • Deadhead spent flowers and remove diseased foliage to redirect energy into fall crops.
  • Water fall seedlings and transplants deeply; soil will dry faster with warm days and low humidity (46%).
  • Mulch newly planted fall crops with 5 cm (2 in) straw to moderate soil temperature swings and retain moisture.
  • Scout for aphids and cabbage moths on brassicas; handpick or use neem oil if needed before transplanting.
  • Cut back perennials (coneflowers, black-eyed Susans) after bloom to tidy beds and prevent self-seeding.

Watch out for

  • Flea beetles and cabbage moths are still active; row cover newly planted brassicas and greens for 3–4 weeks.
  • Nights dip to 13–15°C mid-week; tender annuals (basil, tender herbs) will slow or die—harvest and preserve now.
  • Powdery mildew thrives in cool, humid mornings; space plants for air flow and water at soil level only.

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