What to Plant in September in Zone 4

Here is what you can sow in September if you garden in USDA zone 4. Dates use typical zone 4 frosts, so your own microclimate may shift them by a week or two.

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CropWindowSow between
Lettuce, leafSalad BowlfallJul 12Sep 10
Lettuce, romaineChalupafallJul 12Sep 10
ArugulaAstrofallJul 12Sep 10
Onion, bulbTexas LegendfallJul 31Sep 11
GarlicMusicfallSep 25Oct 10
ShallotAmbitionfallSep 4Oct 9
DillFernleaffallJul 24Sep 4
ChervilCurledfallJul 31Sep 11
LettucefallJul 12Sep 10
OnionfallJul 31Sep 11
Mache (Corn Salad)VitfallJul 27Sep 15
Cress, gardenCurledfallJul 12Sep 10

Zone 4 in September

September in Zone 4: The Last Fast Greens Squeeze In While Garlic Waits

You still have room for one more fast crop

With a first frost that usually holds off until near the end of this month, this zone gets a real fall sowing window that colder zones one step north do not. Arugula, mache, and garden cress on this month's list all finish in 21 to 30 days, which leaves margin even if you sow in the first week rather than rushing.

Lettuce is a tighter fit. A leaf lettuce rated at 45 days sown early in the month finishes right around the historical frost date, so treat any lettuce sown after the first week as a crop that needs row cover standing by, not a sure thing left uncovered. Keep a set of clothespins or binder clips handy for pinning cover edges down on a windy evening, since a cover that blows loose overnight does nothing for the crop underneath it.

Garlic gets its bed ready now, its cloves later

The garlic bed cleared and composted back in August is ready, but the cloves themselves stay in storage a while longer. Planting this early pushes top growth before winter that the first hard freeze then cuts down, so use these weeks to mark rows 12 inches apart and let the soil settle instead.

A little extra spacing here pays back at harvest, since bulbs that fight for room next summer come out noticeably smaller than ones given real room now. Keep the marked bed weed-free through the rest of the month so nothing crowds the cloves once they finally go in, and set the seed garlic itself somewhere cool and dark rather than leaving it on a warm counter, since cloves stored warm can start sprouting weeks before the bed is actually ready for them.

September in zone 4: common questions

What can I plant in September in zone 4?+

In September, USDA zone 4 gardeners can sow Lettuce, leaf, Lettuce, romaine, Arugula, Onion, bulb, Garlic, Shallot, and more. Dates use typical zone 4 frosts, so your own microclimate may shift them by a week or two.

What USDA hardiness zone am I in?+

Zone 4 is one band of the map, but planting time is set by your local frost dates, not the zone number. Enter your ZIP code in the free planner and it uses your actual frost dates, which can differ by weeks within a single zone.

Are these September planting dates exact?+

They are typical zone 4 windows. Two gardens in the same zone can be a week or two apart because of elevation and local climate, so treat these as a starting point and tune them to your ZIP code with the free planner.