What to Plant in September
USDA Zone 9a
Last frost: Feb 1 – Feb 15
Frost-free days: 250–300
The fall growing season is in full swing. Transplant brassicas and direct sow greens, root vegetables, and herbs that thrive in cooler temperatures.
September at a Glance
Indoor
Transplant
Direct Sow
1
5
10
15
20
25
Rosemary
Thyme
Oregano
Sage
Mint
Broccoli
Cauliflower
Cabbage
Kale
Lettuce
Beans (bush)
Beans (pole)
Cucumbers
Summer Squash
Corn
Carrots
Beets
Radishes
Collards
Start Indoors 5
Start these seeds indoors under grow lights or on a sunny windowsill.
Broccoli
Sep 1 – Oct 1
1 per sq ft
60–100 days
Cauliflower
Sep 1 – Oct 1
1 per sq ft
55–100 days
Cabbage
Sep 1 – Oct 1
1 per sq ft
70–100 days
Kale
Sep 1 – Oct 1
1 per sq ft
50–65 days
Lettuce
Sep 1 – Oct 1
4 per sq ft
45–60 days
Transplant 5
Move these seedlings from indoors to your garden beds.
Rosemary
Jan 1 – Dec 31
1 per sq ft
80–120 days
Thyme
Jan 1 – Dec 31
4 per sq ft
70–90 days
Oregano
Jan 1 – Dec 31
1 per sq ft
60–90 days
Sage
Jan 1 – Dec 31
1 per sq ft
75–90 days
Mint
Jan 1 – Dec 31
4 per sq ft
60–90 days
Direct Sow 10
Plant these seeds directly into the soil outdoors.
Mint
Jan 1 – Dec 31
4 per sq ft
60–90 days
Corn
Aug 1 – Sep 1
1 per sq ft
60–100 days
Beans (bush)
Aug 15 – Oct 1
9 per sq ft
50–60 days
Cucumbers
Aug 15 – Sep 15
2 per sq ft
50–70 days
Summer Squash
Aug 15 – Sep 15
Beans (pole)
Sep 1–8
Carrots
Sep 1 – Mar 1
16 per sq ft
70–80 days
Radishes
Sep 1 – Apr 1
16 per sq ft
22–30 days
Collards
Sep 1 – Feb 1
Beets
Sep 15 – Feb 15
9 per sq ft
50–70 days
September Gardening Tips
- Start Lettuce, Broccoli, Cabbage indoors now to give them a head start before transplanting outside.
- Rosemary, Thyme, Oregano can be transplanted outside this month. Harden off seedlings over 5–7 days before planting out.
- Direct sow Corn, Mint, Beans (bush) straight into the garden — no transplanting needed.
- Protect tender crops from early frost with row cover — this can extend your season by several weeks.
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