What to Plant in September in Zone 6: Last Cool Crops and Cover

In USDA zone 6, September is for last lettuce, spinach, and radishes, then cover crops. Skip new tomatoes. Garlic waits until October.

Published 2026-08-28 · Reviewed 2026-08-31 by ThriveThyme

September Zone 6 September zone 6 fall planting

What to Plant in September in Zone 6

In USDA zone 6, September closes the fall sowing window. Direct-sow lettuce, spinach, and arugula in the first part of the month. Fast radishes can still finish if your frost date allows. Then switch spent beds to cover crops. Do not start tomatoes, peppers, or melons from seed.

First frost is often mid-October in many zone 6 gardens, but yards vary. Use My Garden frost settings or the zone 6 fall calendar and count backward. See the zone 6 planting schedule and what to plant in August in zone 6. Colder yards: September zone 5, zone 4, zone 3.

Sow These Now

Lettuce, arugula, spinach: early September is the last typical window. Keep seedbeds cool and moist. Fall lettuce, fall spinach, fall arugula.
Radishes: a short crop if several weeks remain before a hard freeze. Confirm with frost settings.
Kale: late from seed. Transplants can still go in early in the month. Fall kale.
Carrots, beets, turnips: late. Mid to late August was the main window. Skip new rows unless your frost date is later than typical. Fall carrots, fall turnips.
Broccoli and cabbage: too late to seed. Harvest what you transplanted in August. Fall broccoli, fall cabbage.

Cover Crops on Spent Beds

If a bed will not hold greens or garlic, sow cover crops this month. Oats and rye are the usual zone 6 choices. Time sowing against your first hard freeze. When to sow cover crops by zone.

Wait on Garlic

Do not plant garlic in September in zone 6. Cloves need cool soil. Plant mid October through early November. Order seed garlic now if you have not. Garlic by zone.

Harvest Path

Keep picking tomatoes, peppers, beans, and squash until cool nights slow them. Use when to harvest tomatoes and peppers. Pull spent plants so fall greens and cover crops can go in.

Next Steps

This week: sow a short row of lettuce or spinach if you still have weeks before frost. Clear one spent bed for oats or rye. Put seed garlic on the list for October.