Fall · September 8, 2026

Indianapolis, Indiana

Central Hardwoods & Interior Plateaus·Hardiness zone 6b

Now

31°C · Partly cloudy

Today

31° / 18°

Soil 6 cm

25°C

First frost

~51 days (Oct 29)

Gardening in Indianapolis

AI field guide · refreshed weekly

Indianapolis Gardening: Early Fall Planting & Harvest (Week of Sept 8)

You're in zone 6b with 51 days until the average first frost (Oct 29). Soil at 25°C (77°F) is still warm enough for cool-season crops to germinate reliably. This is prime time for fall vegetables—plant now for October and November harvest before hard freezes arrive.

Sow outdoors now

  • Spinach (Bloomsdale, Space or Tyee)

    Direct seed 1.3 cm (½ in) deep in rows 15 cm (6 in) apart. Germinates in 7–10 days at 25°C soil; thin to 10 cm (4 in) spacing. Ready in 40–50 days.

  • Arugula (Roquette)

    Scatter seed 0.6 cm (¼ in) deep, thin to 10 cm (4 in). Grows fast in cool fall weather; harvest leaves at 4–6 weeks or let bolt for peppery flowers.

  • Radish (Cherry Belle, Icicle)

    Sow 1.3 cm (½ in) deep, 5 cm (2 in) apart. Matures in 25–30 days; succession-sow every 2 weeks through late September for continuous harvest.

  • Mâche (Corn Salad)

    Scatter seed 0.6 cm (¼ in) deep in patches. Extremely cold-hardy; germinates slowly but thrives through fall and early winter in zone 6b.

  • Kale (Winterbor, Lacinato)

    Direct seed or transplant seedlings 30 cm (12 in) apart. Flavor improves after frost; harvest outer leaves continuously from late October onward.

Start indoors now

  • Broccoli & Cabbage (Waltham 29, Stonehead)

    Sow in seed trays under lights; transplant outdoors in 4–5 weeks (mid-October) for November harvest before hard freeze. Keep soil moist, 18–21°C (65–70°F).

  • Lettuce (Buttercrunch, Winter Density)

    Start indoors for transplants in 3–4 weeks. Direct seeding outdoors also works, but indoor start gives you a head start in this compressed fall window.

  • Cauliflower (Snowball, Graffiti)

    Sow indoors now; transplant in mid-October for November harvest. Needs consistent moisture and 15–18°C (60–65°F) nights to head properly before frost.

Harvest now

  • Tomatoes (all types)

    Pick all fruit, including green ones. Ripen indoors at 18–21°C (65–70°F) away from direct sun; they'll color in 1–2 weeks. Frost will kill vines by late October.

  • Peppers (sweet & hot)

    Harvest mature peppers now; immature green ones won't ripen before frost. Store at 10–15°C (50–59°F) to extend shelf life.

  • Beans & Summer Squash

    Pick while tender. Both crops slow dramatically as nights cool; pull plants by week's end to redirect energy to fall crops.

Tasks this week

  • Pull spent summer crops (tomatoes, peppers, beans, squash) to clear bed space and reduce disease pressure heading into fall.
  • Amend beds with 5 cm (2 in) compost or aged manure before planting fall crops; cool soil will slow decomposition, so incorporate now.
  • Water transplants and newly seeded beds daily if no rain; 19 mm (¾ in) rain expected Wednesday will help, but don't rely on it.
  • Stake or support fall brassicas (broccoli, cabbage) if you're transplanting; wind gusts to 20 km/h (12 mph) Tuesday can topple young plants.
  • Scout for late-season aphids and Japanese beetles on remaining summer plants; remove by hand or use neem oil if needed before frost.

Watch out for

  • Powdery mildew thrives in cool, humid fall nights—thin crowded plantings and avoid overhead watering to keep foliage dry.
  • Slugs and snails accelerate feeding as temperatures drop; hand-pick at dusk or use beer traps in newly planted beds.
  • Frost can arrive earlier than Oct 29 in low-lying areas or near water—monitor forecasts and have frost cloth ready by mid-October.

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