What to Plant in March
USDA Zone 5b
Last frost: Apr 15 – May 1
Frost-free days: 150–170
Spring is still weeks away outdoors, but indoor seed starting is in full swing. Start tomatoes, peppers, and herbs under lights. Prepare beds for cool-season crops that go out next month.
March at a Glance
Indoor
Transplant
Direct Sow
1
5
10
15
20
25
Sweet Peas
Alyssum
Dahlias
Celosia
Basil
Parsley
Mint
Tarragon
Lemon Balm
Tomatoes
Peppers
Eggplant
Broccoli
Cauliflower
Cabbage
Brussels Sprouts
Kale
Lettuce
Spinach
Peas
Swiss Chard
Kohlrabi
Start Indoors 19
Start these seeds indoors under grow lights or on a sunny windowsill.
Parsley
Feb 15 – Mar 1
4 per sq ft
70–90 days
Peppers
Feb 15 – Mar 1
1 per sq ft
60–100 days
Eggplant
Feb 15 – Mar 1
1 per sq ft
70–90 days
Broccoli
Feb 15 – Mar 1
1 per sq ft
60–100 days
Cauliflower
Feb 15 – Mar 1
1 per sq ft
55–100 days
Cabbage
Feb 15 – Mar 1
1 per sq ft
70–100 days
Brussels Sprouts
Feb 15 – Mar 1
1 per sq ft
80–110 days
Alyssum
Mar 1–8
Dahlias
Mar 1–8
Mint
Mar 1–8
4 per sq ft
60–90 days
Tarragon
Mar 1–8
Lemon Balm
Mar 1–8
Tomatoes
Mar 1–15
1 per sq ft
65–80 days
Kale
Mar 1–15
1 per sq ft
50–65 days
Lettuce
Mar 1–15
4 per sq ft
45–60 days
Kohlrabi
Mar 1–8
Celosia
Mar 15–22
Basil
Mar 15 – Apr 1
4 per sq ft
25–35 days
Swiss Chard
Mar 15–22
4 per sq ft
50–60 days
Direct Sow 3
Plant these seeds directly into the soil outdoors.
Sweet Peas
Mar 15 – Apr 1
Spinach
Mar 15 – Apr 15
9 per sq ft
35–50 days
Peas
Mar 15 – Apr 15
8 per sq ft
55–70 days
March Gardening Tips
- Start Lettuce, Broccoli, Cabbage indoors now to give them a head start before transplanting outside.
- Direct sow Peas, Spinach, Sweet Peas straight into the garden — no transplanting needed.
- Add compost to beds now so nutrients are available when planting time arrives.
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