What to Plant in May
Tucson, AZ · Zone 9a
Last frost: Feb 15
Frost-free days: 289
Full summer mode — everything warm-season is in the ground and growing. Keep succession planting beans, squash, and cucumbers. Start heat-tolerant crops for midsummer harvests.
May at a Glance
Indoor
Transplant
Direct Sow
1
5
10
15
20
25
Start Indoors 19
Start these seeds indoors under grow lights or on a sunny windowsill.
Chives
Jan 1 – Dec 31
9 per sq ft
60–90 days
Mint
Jan 1 – Dec 31
4 per sq ft
60–90 days
Oregano
Jan 1 – Jun 8
1 per sq ft
60–90 days
Sage
Jan 1 – May 23
1 per sq ft
75–90 days
Thyme
Jan 1 – May 16
4 per sq ft
70–90 days
Artichoke
Jan 1 – Jun 23
1 per sq ft
85–100 days
Leek
Jan 1 – Dec 31
4 per sq ft
90–150 days
Onion
Jan 1 – Dec 31
9 per sq ft
100–120 days
Strawberry
Jan 1 – Dec 31
4 per sq ft
60–90 days
Tomato
Jan 24 – May 16
1 per sq ft
65–80 days
Growing guide
Sunflower
Feb 8 – Jun 8
1 per sq ft
70–100 days
Pumpkin
Feb 22 – May 16
¼ per sq ft
85–120 days
Squash
Feb 22 – Jul 16
1 per sq ft
45–65 days
Zucchini
Feb 22 – Jul 16
1 per sq ft
45–60 days
Basil
Mar 1 – Jul 31
4 per sq ft
25–35 days
Cucumber
Mar 17 – Jun 30
2 per sq ft
50–70 days
Growing guide
Melon
Mar 17 – May 23
½ per sq ft
70–90 days
Okra
Mar 17 – Jun 15
1 per sq ft
50–65 days
Watermelon
Mar 24 – May 23
¼ per sq ft
70–90 days
Transplant 31
Move these seedlings from indoors to your garden beds.
Chives
Jan 1 – Dec 31
9 per sq ft
60–90 days
Lavender
Jan 1 – Jun 23
1 per sq ft
90–120 days
Mint
Jan 1 – Dec 31
4 per sq ft
60–90 days
Oregano
Jan 1 – Jul 31
1 per sq ft
60–90 days
Parsley
Jan 1 – May 31
4 per sq ft
70–90 days
Rosemary
Jan 1 – Jun 30
1 per sq ft
80–120 days
Sage
Jan 1 – Jul 16
1 per sq ft
75–90 days
Thyme
Jan 1 – Jul 23
4 per sq ft
70–90 days
Artichoke
Jan 1 – Aug 31
1 per sq ft
85–100 days
Broccoli
Jan 1 – May 8
1 per sq ft
60–100 days
Brussels Sprouts
Jan 1 – May 8
1 per sq ft
80–110 days
Cabbage
Jan 1 – May 8
1 per sq ft
70–100 days
Cauliflower
Jan 1 – May 8
1 per sq ft
55–100 days
Celery
Jan 1 – May 8
4 per sq ft
80–120 days
Kale
Jan 1 – May 31
1 per sq ft
50–65 days
Leek
Jan 1 – Dec 31
4 per sq ft
90–150 days
Onion
Jan 1 – Dec 31
9 per sq ft
100–120 days
Strawberry
Jan 1 – Dec 31
4 per sq ft
60–90 days
Swiss Chard
Jan 1 – May 31
4 per sq ft
50–60 days
Sunflower
Mar 1 – Jun 30
1 per sq ft
70–100 days
Pumpkin
Mar 17 – Jun 8
¼ per sq ft
85–120 days
Squash
Mar 17 – Aug 8
1 per sq ft
45–65 days
Tomato
Mar 17 – Jul 8
1 per sq ft
65–80 days
Growing guide
Zucchini
Mar 17 – Aug 8
1 per sq ft
45–60 days
Cucumber
Apr 9 – Jul 23
2 per sq ft
50–70 days
Growing guide
Eggplant
Apr 9 – Jun 23
1 per sq ft
70–90 days
Pepper
Apr 9 – Jun 30
1 per sq ft
60–100 days
Growing guide
Basil
Apr 16 – Sep 15
4 per sq ft
25–35 days
Melon
Apr 16 – Jun 23
½ per sq ft
70–90 days
Okra
Apr 24 – Jul 23
1 per sq ft
50–65 days
Watermelon
Apr 24 – Jun 23
¼ per sq ft
70–90 days
Direct Sow 6
Plant these seeds directly into the soil outdoors.
Beet
Jan 1 – May 16
9 per sq ft
50–70 days
Carrot
Jan 1 – May 16
16 per sq ft
70–80 days
Garlic
Jan 1 – Nov 30
9 per sq ft
180–240 days
Potato
Jan 1 – May 16
1 per sq ft
70–150 days
Turnip
Jan 1 – May 16
9 per sq ft
30–60 days
Dill
Mar 1 – May 16
4 per sq ft
40–60 days
May Gardening Tips
- Start Tomato, Cucumber, Squash indoors now to give them a head start before transplanting outside.
- Tomato, Pepper, Cucumber 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.
- Mulch around transplants with 2–3 inches of straw or shredded leaves to retain moisture and suppress weeds.
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