What to Plant in December
USDA Zone 9a
Last frost: Feb 1 – Feb 15
Frost-free days: 250–300
Winter gardening continues — harvest cool-season greens and root vegetables. Plan next year's layout and order seeds early for the best selection.
December at a Glance
Indoor
Transplant
Direct Sow
1
5
10
15
20
25
Cilantro
Dill
Rosemary
Thyme
Oregano
Sage
Mint
Tomatoes
Peppers
Eggplant
Lettuce
Spinach
Peas
Carrots
Beets
Radishes
Onions (sets)
Collards
Start Indoors 3
Start these seeds indoors under grow lights or on a sunny windowsill.
Tomatoes
Dec 15 – Jan 15
1 per sq ft
65–80 days
Peppers
Dec 15 – Jan 15
1 per sq ft
60–100 days
Eggplant
Dec 15 – Jan 15
1 per sq ft
70–90 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 11
Plant these seeds directly into the soil outdoors.
Mint
Jan 1 – Dec 31
4 per sq ft
60–90 days
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
Cilantro
Oct 1 – Feb 1
9 per sq ft
30–45 days
Dill
Oct 1 – Mar 1
4 per sq ft
40–60 days
Lettuce
Oct 1 – Feb 1
4 per sq ft
45–60 days
Spinach
Oct 1 – Feb 1
9 per sq ft
35–50 days
Onions (sets)
Oct 1 – Jan 1
9 per sq ft
100–120 days
Peas
Nov 1 – Jan 15
8 per sq ft
55–70 days
December Gardening Tips
- Start Eggplant, Tomatoes, Peppers 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 Lettuce, Peas, Spinach straight into the garden — no transplanting needed.
- Get a soil test now — results come back fast in the off-season and you can amend before spring.
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