What to plant in March in Maine
In Maine (ME), March sits about 9 weeks before the average last frost (May 14). The state averages 134 frost-free days a year (last frost May 14, first frost September 25; USDA zones 3b, 4a, 4b, 5a, 5b, 6a).
29 crops have a sowing or planting window this month - and 5 of those windows close during March.
Dates here come from Maine frost dates (last frost May 14, first frost Sep 25). For one crop in detail, see when to plant onion, eggplant or bell pepper in Maine.
Maine: planting activity through the year
Last chance in March
Celeriac (start seeds indoors, by Mar 5) · Celery (start seeds indoors, by Mar 12) · Leek (start seeds indoors, by Mar 12) · Onion (start seeds indoors, by Mar 12) · Rosemary (start seeds indoors, by Mar 12)
Start seeds indoors in March (29)
Indoor sowings for transplants later. Six to eight weeks under lights is typical for tomatoes and peppers; onions and leeks need longer.
| Crop | What to do | Window | This month |
|---|---|---|---|
| Celeriac | Start seeds indoors | Feb 19 – Mar 5 | Last chance - ends Mar 5 |
| Celery | Start seeds indoors | Feb 26 – Mar 12 | Last chance - ends Mar 12 |
| Leek | Start seeds indoors | Feb 26 – Mar 12 | Last chance - ends Mar 12 |
| Onion | Start seeds indoors | Feb 26 – Mar 12 | Last chance - ends Mar 12 |
| Rosemary | Start seeds indoors | Feb 26 – Mar 12 | Last chance - ends Mar 12 |
| Eggplant | Start seeds indoors | Mar 5 – Mar 19 | Mar 5 – Mar 19 |
| Parsley | Start seeds indoors | Mar 5 – Mar 19 | Mar 5 – Mar 19 |
| Shallot | Start seeds indoors | Mar 5 – Mar 19 | Mar 5 – Mar 19 |
| Bell Pepper | Start seeds indoors | Mar 12 – Mar 26 | Mar 12 – Mar 26 |
| Chili Pepper | Start seeds indoors | Mar 12 – Mar 26 | Mar 12 – Mar 26 |
| Ginger | Start seeds indoors | Mar 12 – Mar 26 | Mar 12 – Mar 26 |
| Green Onion / Scallion | Start seeds indoors | Mar 12 – Mar 26 | Mar 12 – Mar 26 |
| Mint | Start seeds indoors | Mar 12 – Mar 26 | Mar 12 – Mar 26 |
| Oregano | Start seeds indoors | Mar 12 – Mar 26 | Mar 12 – Mar 26 |
| Sage | Start seeds indoors | Mar 12 – Mar 26 | Mar 12 – Mar 26 |
| Tarragon | Start seeds indoors | Mar 12 – Mar 26 | Mar 12 – Mar 26 |
| Thyme | Start seeds indoors | Mar 12 – Mar 26 | Mar 12 – Mar 26 |
| Turmeric | Start seeds indoors | Mar 12 – Mar 26 | Mar 12 – Mar 26 |
| Ground Cherry | Start seeds indoors | Mar 19 – Apr 2 | Opens Mar 19 |
| Lemon Balm | Start seeds indoors | Mar 19 – Apr 2 | Opens Mar 19 |
| Shiso (Perilla) | Start seeds indoors | Mar 19 – Apr 2 | Opens Mar 19 |
| Sweet Marjoram | Start seeds indoors | Mar 19 – Apr 2 | Opens Mar 19 |
| Tomatillo | Start seeds indoors | Mar 19 – Apr 2 | Opens Mar 19 |
| Tomato | Start seeds indoors | Mar 19 – Apr 2 | Opens Mar 19 |
| Broccoli | Start seeds indoors | Mar 26 – Apr 9 | Opens Mar 26 |
| Brussels Sprouts | Start seeds indoors | Mar 26 – Apr 9 | Opens Mar 26 |
| Cabbage | Start seeds indoors | Mar 26 – Apr 9 | Opens Mar 26 |
| Cauliflower | Start seeds indoors | Mar 26 – Apr 9 | Opens Mar 26 |
| Kale | Start seeds indoors | Mar 26 – Apr 9 | Opens Mar 26 |
Planting dates for popular crops in Maine
Every crop has its own full-year dates for Maine: indoor start, transplant or direct sowing, and harvest.
Seed-starting season: March garden jobs in Maine
- Start 29 crops indoors this month, including celeriac, celery, leek, onion. Use a sterile mix and good light - see starting seeds indoors.
- 9 weeks until the average last frost (May 14). The seed-starting calculator works out each crop's exact sowing date from it.
- Keep seedlings from stretching: lights 2-3 inches above the leaves for 14-16 hours a day, and a fan or a daily brush of the hand across the tops.
- Prepare beds as soon as the soil crumbles instead of smearing when squeezed - working wet soil ruins its structure for the season.
USDA zone chart for Maine
Maine spans USDA zones 3b, 4a, 4b, 5a, 5b, 6a. Colder zones, usually higher or further inland, have a later last spring frost and an earlier first fall frost than the state average.
Questions gardeners ask
What vegetables can I plant in Maine in March?
29 crops have a window in March: celeriac, celery, leek, onion, rosemary, eggplant, parsley, shallot, bell pepper, chili pepper and more. The tables above give the exact dates for each.
Is it too late to plant tomatoes in Maine in March?
No - start seeds indoors runs Mar 19 – Apr 2 in Maine.
Is it too late to plant lettuce in Maine in March?
Not too late - it's actually a little early. In Maine the next lettuce window opens around April 9: start seeds indoors.
When is the first frost in Maine?
The statewide average first fall frost is around September 25 and the last spring frost around May 14. Your town can be a week or two either side - look yours up by ZIP code.
What should I start indoors in March in Maine?
Celeriac (Feb 19 – Mar 5), Celery (Feb 26 – Mar 12), Leek (Feb 26 – Mar 12), Onion (Feb 26 – Mar 12), Rosemary (Feb 26 – Mar 12), Eggplant (Mar 5 – Mar 19), Parsley (Mar 5 – Mar 19), Shallot (Mar 5 – Mar 19), Bell Pepper (Mar 12 – Mar 26), Chili Pepper (Mar 12 – Mar 26), Ginger (Mar 12 – Mar 26), Green Onion / Scallion (Mar 12 – Mar 26), Mint (Mar 12 – Mar 26), Oregano (Mar 12 – Mar 26), Sage (Mar 12 – Mar 26), Tarragon (Mar 12 – Mar 26), Thyme (Mar 12 – Mar 26), Turmeric (Mar 12 – Mar 26), Ground Cherry (Mar 19 – Apr 2), Lemon Balm (Mar 19 – Apr 2), Shiso (Perilla) (Mar 19 – Apr 2), Sweet Marjoram (Mar 19 – Apr 2), Tomatillo (Mar 19 – Apr 2), Tomato (Mar 19 – Apr 2), Broccoli (Mar 26 – Apr 9), Brussels Sprouts (Mar 26 – Apr 9), Cabbage (Mar 26 – Apr 9), Cauliflower (Mar 26 – Apr 9), Kale (Mar 26 – Apr 9).
What to plant in March in other states
Dates are computed from Maine’s statewide average frost dates (from NOAA/NCEI climate normals) and each crop’s timing in our crop database. Your garden may be a week or two either side - for dates tuned to your ZIP code, use the planting calendar.