Maine · zones 3b–6a
When to plant basil in Maine.
Sow or transplant between May 29 to Aug 14 in a typical year, keyed to Maine's median last frost around May 8. Dates below are state medians; your ZIP code shifts them by days to weeks.
The 2026 windows
Basil dates for a typical Maine season.
1 · Start indoors
Apr 17 to Jul 3
About 6 weeks before set-out. Warm spot, real light.
2 · Set out
May 29 to Aug 14
Keyed to the ~May 8 last frost. Sow 0.25" deep, 8" apart.
Harvest
~40 days later
~0.5 lb per plant over ~12 weeks.
Maine spans more than one climate: Zone 5 is the most common zone, but the state runs 3b to 6a. That's why the planner works from your ZIP code's frost dates, not your zone: mountain and coastal gardens in the same state can be three weeks apart.
In Maine: watch for
The pests that find basil here.
A middle-length season, about 152 frost-free days, means basil overlaps aphids for a stretch each summer. Check plants every week or two and treat early.
Fine webbing and pale stippling in hot, dry spells.
Organic fix: Spray the undersides with water, then insecticidal soap or neem.
Yellowing with gray fuzz underneath, or white powder on top.
Organic fix: Space for airflow, water at the base, spray neem.
Metallic beetles chewing basil and mint leaves to lace.
Organic fix: Handpick into soapy water in the morning; neem.
Your season math: Maine gives basil about 152 frost-free days, and it needs roughly 40 days to a first harvest. It's a one-planting crop, so time that single sowing well.
Planting basil in Maine: questions
When should I plant basil in Maine?+
In a typical Maine year, sow basil or set out transplants between May 29 to Aug 14, keyed to the state's median last frost around May 8. Your exact dates shift with your ZIP code and microclimate.
When do I start basil seeds indoors in Maine?+
Start seeds inside about 6 weeks before set-out: roughly Apr 17 to Jul 3 for a typical Maine season.
What USDA zone is Maine?+
Maine spans zones 3b–6a, mostly zone 5. But frost dates, not zones, set planting time. The free planner uses your ZIP code's actual frost dates.
How many basil plants do I need?+
Depends who you're feeding. The crop page has exact counts per household size, or the free planner does the math for your family in about 60 seconds.