Fall · September 8, 2026

Saint Louis, Missouri

Central Hardwoods & Interior Plateaus·Hardiness zone 7a

Now

34°C · Clear

Today

35° / 17°

Soil 6 cm

26°C

First frost

~55 days (Nov 2)

Gardening in Saint Louis

AI field guide · refreshed weekly

Saint Louis Gardening: Early September — Plant Fall Crops, Extend the Season

Zone 7a, first fall frost Nov 2 (55 days away). Soil at 26°C is ideal for germination of cool-season crops. You have a solid window to establish greens, brassicas, and root vegetables before soil temps drop below 15°C in late October. Spring frost (Apr 13) means your spring-planted perennials are well-established; focus now on fall succession.

Sow outdoors now

  • Lettuce & Salad Mixes

    Sow 'Buttercrunch', 'Oakleaf', or 'Lollo Rosso' directly; germinates in 7–10 days at 26°C soil. Thin to 15 cm spacing; ready in 40–50 days before hard frost.

  • Spinach

    Direct sow 'Space' or 'Bloomsdale'; prefers 15–20°C but germinates now. Succession-sow every 10 days through mid-September for continuous harvest into November.

  • Arugula

    Fast grower (30 days to harvest). Sow 'Roquette' or 'Astro' densely; thin to 10 cm. Tolerates light frost, so late plantings extend into November.

  • Radish

    Spring varieties like 'Cherry Belle' mature in 25 days; sow now for October harvest. Loose soil essential; thin to 5 cm spacing.

  • Turnip & Rutabaga

    Sow 'Purple Top' turnip or 'Laurentian' rutabaga; both need 60–80 days. Plant by Sept 15 to mature before hard freeze; thin to 15 cm.

Start indoors now

  • Brassicas (Cabbage, Broccoli, Kale)

    Start 'Tatsoi', 'Winterbor' kale, or 'Gonzales' cabbage indoors in seed trays; transplant at 4–6 weeks (late Sept/early Oct) into garden. Kale especially cold-hardy for November–December harvest.

  • Cauliflower

    Start 'Snowball' or 'Graffiti' now; transplant in 5 weeks. Needs consistent moisture and 60–70 days to head; timing is tight but doable for early November harvest.

  • Onion Sets (Spring Onions)

    Start 'Evergreen Hardy' or 'Bunching' bunching onions indoors for transplant in 3–4 weeks; overwinter in garden for early spring bulbing.

Harvest now

  • Tomatoes & Peppers

    Pick ripe fruit before first frost (Nov 2). Green tomatoes ripen indoors in 2–3 weeks at room temperature; peppers slow after 25°C nights end (mid-Sept).

  • Summer Squash & Zucchini

    Harvest daily; plants decline as nights cool. Remove spent vines by late September to reduce powdery mildew and redirect energy.

  • Beans & Peas

    Pick snap beans and peas while tender. Frost will kill plants; harvest all usable pods by late October.

Tasks this week

  • Deadhead spent flowers and remove diseased foliage to reduce pest/disease pressure as humidity drops.
  • Water deeply 2–3 times this week (forecast shows rain only Sept 10 & 14); soil at 26°C dries fast in low humidity.
  • Mulch newly sown beds with 2–3 cm compost to retain moisture and regulate soil temperature as nights cool.
  • Scout for Japanese beetles, spider mites, and powdery mildew on squash and beans; remove affected leaves.
  • Divide and transplant spring-blooming perennials (daylilies, coneflowers) by late September for root establishment before winter.

Watch out for

  • Powdery mildew thrives in warm days (35°C) and cool nights; thin foliage for airflow and avoid overhead watering.
  • Soil dries quickly at 26°C with 34% humidity and 8 km/h wind—check moisture daily, especially for newly sown seeds.
  • Frost risk jumps after Nov 2; tender crops (tomatoes, peppers, basil) must be harvested or protected by then.

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