What to Plant in August

Phoenix, AZ · Zone 9b

Last frost: Feb 5 Frost-free days: 313

Late summer is prime time for starting your fall garden. Sow cool-season crops indoors or direct sow fast-maturing varieties. The heat will ease soon.

August at a Glance

Indoor Transplant Direct Sow
1 5 10 15 20 25
Basil
Chives
Lavender
Mint
Oregano
Parsley
Rosemary
Sage
Thyme
Artichoke
Broccoli
Brussels Sprouts
Cabbage
Cauliflower
Celery
Garlic
Kale
Leek
Onion
Squash
Strawberry
Zucchini

Start Indoors 19

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
Lavender
Lavender
Jan 1 – Dec 31
1 per sq ft 90–120 days
Mint
Mint
Jan 1 – Dec 31
4 per sq ft 60–90 days
Oregano
Oregano
Jan 1 – Dec 31
1 per sq ft 60–90 days
Rosemary
Rosemary
Jan 1 – Dec 31
1 per sq ft 80–120 days
Sage
Sage
Jan 1 – Dec 31
1 per sq ft 75–90 days
Thyme
Thyme
Jan 1 – Dec 31
4 per sq ft 70–90 days
Artichoke
Artichoke
Jan 1 – Dec 31
1 per sq ft 85–100 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
Feb 15 – Aug 8
4 per sq ft 25–35 days
Brussels Sprouts
Brussels Sprouts
Jun 9 – Aug 23
1 per sq ft 80–110 days
Parsley
Parsley
Jul 24 – Dec 31
4 per sq ft 70–90 days
Celery
Celery
Jul 24 – Dec 31
4 per sq ft 80–120 days

Later this month

Kale
Kale
Aug 17 – Dec 31
1 per sq ft 50–65 days
Broccoli
Broccoli
Aug 24 – Dec 31
1 per sq ft 60–100 days
Cabbage
Cabbage
Aug 24 – Dec 31
1 per sq ft 70–100 days
Cauliflower
Cauliflower
Aug 24 – Dec 31
1 per sq ft 55–100 days

Transplant 14

Move these seedlings from indoors to your garden beds.

Chives
Chives
Jan 1 – Dec 31
9 per sq ft 60–90 days
Lavender
Lavender
Jan 1 – Dec 31
1 per sq ft 90–120 days
Mint
Mint
Jan 1 – Dec 31
4 per sq ft 60–90 days
Oregano
Oregano
Jan 1 – Dec 31
1 per sq ft 60–90 days
Rosemary
Rosemary
Jan 1 – Dec 31
1 per sq ft 80–120 days
Sage
Sage
Jan 1 – Dec 31
1 per sq ft 75–90 days
Thyme
Thyme
Jan 1 – Dec 31
4 per sq ft 70–90 days
Artichoke
Artichoke
Jan 1 – Dec 31
1 per sq ft 85–100 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
Squash
Squash
Mar 1 – Aug 8
1 per sq ft 45–65 days
Zucchini
Zucchini
Mar 1 – Aug 8
1 per sq ft 45–60 days
Basil
Basil
Apr 1 – Sep 23
4 per sq ft 25–35 days

Direct Sow 1

Plant these seeds directly into the soil outdoors.

Garlic
Garlic
Jan 1 – Nov 23
9 per sq ft 180–240 days

August Gardening Tips

  • Start Broccoli, Cabbage, Kale indoors now to give them a head start before transplanting outside.
  • Squash, Zucchini, Strawberry can be transplanted outside this month. Harden off seedlings over 5–7 days before planting out.
  • Direct sow Garlic straight into the garden — no transplanting needed.
  • Count backwards from your first frost date to determine the last safe date for starting fall crops.

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