What to Plant in September

Tucson, AZ · Zone 9a

Last frost: Feb 15 Frost-free days: 289

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
Chives
Mint
Parsley
Beet
Broccoli
Cabbage
Carrot
Cauliflower
Garlic
Kale
Leek
Lettuce
Onion
Potato
Strawberry
Swiss Chard
Turnip

Start Indoors 12

Start these seeds indoors under grow lights or on a sunny windowsill.

Plant now

Chives
Chives
Jan 1 – Dec 31
9 per sq ft 60–90 days
Mint
Mint
Jan 1 – Dec 31
4 per sq ft 60–90 days
Leek
Leek
Jan 1 – Dec 31
4 per sq ft 90–150 days
Onion
Onion
Jan 1 – Dec 31
9 per sq ft 100–120 days
Strawberry
Strawberry
Jan 1 – Dec 31
4 per sq ft 60–90 days
Parsley
Parsley
Jul 9 – Dec 31
4 per sq ft 70–90 days
Kale
Kale
Aug 1 – Dec 31
1 per sq ft 50–65 days
Broccoli
Broccoli
Aug 17 – Dec 31
1 per sq ft 60–100 days
Cabbage
Cabbage
Aug 17 – Dec 31
1 per sq ft 70–100 days
Cauliflower
Cauliflower
Aug 17 – Dec 31
1 per sq ft 55–100 days
Swiss Chard
Swiss Chard
Aug 17 – Dec 31
4 per sq ft 50–60 days

Later this month

Lettuce
Lettuce
Sep 24 – Dec 31
4 per sq ft 45–60 days

Transplant 9

Move these seedlings from indoors to your garden beds.

Plant now

Chives
Chives
Jan 1 – Dec 31
9 per sq ft 60–90 days
Mint
Mint
Jan 1 – Dec 31
4 per sq ft 60–90 days
Leek
Leek
Jan 1 – Dec 31
4 per sq ft 90–150 days
Onion
Onion
Jan 1 – Dec 31
9 per sq ft 100–120 days
Strawberry
Strawberry
Jan 1 – Dec 31
4 per sq ft 60–90 days
Basil
Basil
Apr 16 – Sep 15
4 per sq ft 25–35 days

Later this month

Parsley
Parsley
Sep 16 – Dec 31
4 per sq ft 70–90 days
Kale
Kale
Sep 16 – Dec 31
1 per sq ft 50–65 days
Swiss Chard
Swiss Chard
Sep 16 – Dec 31
4 per sq ft 50–60 days

Direct Sow 5

Plant these seeds directly into the soil outdoors.

Plant now

Garlic
Garlic
Jan 1 – Nov 30
9 per sq ft 180–240 days

Later this month

Beet
Beet
Sep 16 – Dec 31
9 per sq ft 50–70 days
Carrot
Carrot
Sep 16 – Dec 31
16 per sq ft 70–80 days
Potato
Potato
Sep 16 – Dec 31
1 per sq ft 70–150 days
Turnip
Turnip
Sep 16 – Dec 31
9 per sq ft 30–60 days

September Gardening Tips

  • Start Lettuce, Broccoli, Cabbage indoors now to give them a head start before transplanting outside.
  • Kale, Strawberry, Chives can be transplanted outside this month. Harden off seedlings over 5–7 days before planting out.
  • Direct sow Carrot, Potato, Garlic 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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