What to Plant in September
USDA Zone 10b
Last frost: Jan 15 – Feb 1
Frost-free days: 300–365
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
Basil
Rosemary
Thyme
Oregano
Mint
Lemongrass
Broccoli
Cauliflower
Cabbage
Kale
Lettuce
Beans (bush)
Beans (pole)
Cucumbers
Summer Squash
Corn
Carrots
Tropical Crops
Start Indoors 5
Start these seeds indoors under grow lights or on a sunny windowsill.
Broccoli
Aug 15 – Sep 15
1 per sq ft
60–100 days
Cauliflower
Aug 15 – Sep 15
1 per sq ft
55–100 days
Cabbage
Aug 15 – Sep 15
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 10
Move these seedlings from indoors to your garden beds.
Basil
Jan 1 – Dec 31
4 per sq ft
25–35 days
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
Mint
Jan 1 – Dec 31
4 per sq ft
60–90 days
Lemongrass
Jan 1 – Dec 31
Tropical Crops
Jan 1 – Dec 31
Broccoli
Sep 15 – Nov 1
1 per sq ft
60–100 days
Cauliflower
Sep 15 – Nov 1
1 per sq ft
55–100 days
Cabbage
Sep 15 – Nov 1
1 per sq ft
70–100 days
Direct Sow 9
Plant these seeds directly into the soil outdoors.
Basil
Jan 1 – Dec 31
4 per sq ft
25–35 days
Mint
Jan 1 – Dec 31
4 per sq ft
60–90 days
Tropical Crops
Jan 1 – Dec 31
Beans (bush)
Sep 1 – Nov 1
9 per sq ft
50–60 days
Cucumbers
Sep 1 – Oct 1
2 per sq ft
50–70 days
Summer Squash
Sep 1 – Oct 1
Corn
Sep 1 – Oct 1
1 per sq ft
60–100 days
Beans (pole)
Sep 15 – Oct 15
Carrots
Sep 15 – Mar 1
16 per sq ft
70–80 days
September Gardening Tips
- Start Lettuce, Broccoli, Cabbage indoors now to give them a head start before transplanting outside.
- Broccoli, Cabbage, Cauliflower can be transplanted outside this month. Harden off seedlings over 5–7 days before planting out.
- Direct sow Corn, Basil, Mint 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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