My Planting Calendar

What to plant in September in zone 3

USDA zone 3 has winter lows of -40 to -30°F, a typical last spring frost around May 15 and first fall frost around Sep 15, roughly 120 frost-free days. September is the "after the first frost" there.

2 crops have a sowing or planting window this month: shallot, garlic.

Dates come from the typical frost dates of USDA zone 3 (last frost May 15, first frost Sep 15). A zone covers many climates, so for dates tuned to your town use the planting calendar, or pick your state below.

After the first frostSow or plant: 2Start indoors: 0Harvesting: 51

Zone 3: planting activity through the year

0
5
29
65
91
69
34
8
2
2
0
0
JanFebMarAprMayJunJulAugSepOctNovDec
Frost riskFrost-free: May 15 – Sep 15
Bars count the vegetables, herbs and fruit with a sowing or planting window in each month, from the state’s average frost dates. 2 have one in September; the busiest month is May (91).

For fall and winter harvests (2)

Sowings counted back from zone 3's first fall frost, so the crop matures before the cold - or, for garlic and similar, planted after it.

CropWhat to doWindowThis month
ShallotPlant in fall (after first frost)Sep 19 – Oct 6Opens Sep 19
GarlicPlant in fall (after first frost)Sep 26 – Oct 13Opens Sep 26

Harvesting in September

First harvests expected this month from crops sown or planted on time earlier in the season.

Cucumber · Aug 2 – Sep 8Lima Bean · Aug 2 – Sep 1Broccoli · Aug 5 – Sep 16Cauliflower · Aug 5 – Sep 21Cabbage · Aug 5 – Oct 1Chili Pepper · Aug 7 – Sep 6Watermelon · Aug 7 – Sep 6Bush Bean · Aug 9 – Sep 5Kale · Aug 9 – Sep 10Leek · Aug 9 – Sep 28Winter Squash · Aug 10 – Sep 9Lettuce · Aug 10 – Sep 26Brussels Sprouts · Aug 14 – Sep 30Bok Choy / Pak Choi · Aug 15 – Sep 16Mizuna · Aug 15 – Sep 11Swiss Chard · Aug 16 – Sep 12Parsnip · Aug 16 – Sep 15Napa Cabbage · Aug 16 – Sep 27Mustard Greens · Aug 17 – Sep 18Fennel (Bulb) · Aug 17 – Sep 28Cilantro / Coriander · Aug 18 – Sep 29Carrot · Aug 19 – Sep 25Radicchio · Aug 19 – Oct 15Salsify · Aug 19 – Sep 28Pumpkin · Aug 20 – Sep 19Dill · Aug 20 – Sep 26Rosemary · Aug 20 – Sep 19Rapini (Broccoli Raab) · Aug 20 – Sep 26Pea · Aug 21 – Sep 22Collard Greens · Aug 21 – Sep 27Tatsoi · Aug 22 – Sep 23Beet · Aug 23 – Sep 29Radish · Aug 23 – Sep 17Celery · Aug 23 – Oct 2Celeriac · Aug 23 – Sep 12Spinach · Aug 24 – Sep 18Arugula · Aug 24 – Sep 20Kohlrabi · Aug 25 – Sep 26Mache (Corn Salad) · Aug 25 – Sep 26Turnip · Aug 27 – Oct 3Chervil · Aug 27 – Oct 3Luffa (Loofah Gourd) · Aug 27 – Oct 26Rutabaga · Aug 28 – Sep 24Peanut · Aug 30 – Oct 19Sweet Potato · Sep 3 – Oct 3Borage · Sep 4 – Oct 11Parsley · Sep 5 – Oct 12Green Onion / Scallion · Sep 9 – Oct 16Watercress · Sep 13 – Oct 10Endive & Escarole · Sep 20 – Oct 22Fava Bean (Broad Bean) · Sep 24 – Oct 26

After the first frost: September garden jobs in zone 3

  1. The average first frost (September 15) has passed - pull frost-killed tender plants and compost the healthy ones; bin or burn anything that had blight or mildew.
  2. Plant garlic now (Sep 26 – Oct 13): single cloves, pointy end up, 2 inches deep and 6 inches apart, then mulch.
  3. Leave cold-hardy roots (carrots, parsnips, leeks) in the ground under a thick mulch and dig them as needed.
  4. Clean and oil tools, drain hoses, and note what worked this year while you still remember - it makes next year's plan far easier.

Questions gardeners ask

What can I plant in zone 3 in September?

2 crops have a window in September: shallot, garlic. The tables above give the exact dates for each.

When are the last and first frost in zone 3?

The typical last spring frost is around May 15 and the first fall frost around Sep 15. These are broad zone averages, so your own town can be a week or two either side: look yours up by ZIP code in the planting calendar.

What can I harvest in zone 3 in September?

From plantings made on time: cucumber, lima bean, broccoli, cauliflower, cabbage, chili pepper, watermelon, bush bean, kale, leek.

September in states with land in zone 3

AlaskaColoradoIdahoMaineMontanaNew HampshireNew YorkNorth DakotaSouth DakotaVermontWisconsinWyoming

Zone 3 in other months

FebruaryMarchAprilMayJuneJulyAugustOctoberZone 3 overview →

What to plant in September in other zones

Zone 4Zone 5Zone 6Zone 7Zone 8Zone 9Zone 10All states →

Dates are computed from the zone’s typical frost dates and each crop’s timing in our crop database. Your garden may be a week or two either side.