When to plant basil in Maine
Maine’s average last spring frost is May 14, and the first fall frost typically arrives around September 25 — about 134 frost-free days (USDA zones 3b, 4a, 4b, 5a, 5b, 6a). Basil needs 30–60 days to mature, which fits comfortably within Maine's growing season.
When to plant basil in Maine: the short answer
For a spring planting, plant out May 21 – Jun 7, with seeds started indoors Apr 2 – Apr 16. Wait until the soil is at least 65°F and frost is over.
Succession sow again in Maine: Jun 18 · Jul 9 · Jul 30
Windows are ~1–2 week bands around each date. Frost dates are a statewide average from NOAA/NCEI normals; your town may differ by two weeks or more. Calendar year 2026.
How to grow basil in Maine, step by step
- Start seeds indoors (Apr 2 – Apr 16). Sow seeds ⅛ inch deep in seed-starting mix under bright light. They take 5-10 days to sprout, fastest in soil around 80°F. Harden seedlings off for a week before they go outside.
- Prepare the bed. It needs at least six to eight hours of direct sun a day and loose soil at least 10 inches deep, with a pH between 6.0 and 7.0. Dig in compost before planting.
- Plant out (May 21 – Jun 7). Space plants about 10 inches apart in rows 12 inches apart. It is killed by frost, so nothing goes outside until the danger has passed.
- Water and feed. Give it steady, even moisture, about an inch of water a week from rain or the hose.
- Watch for pests and problems. Pests: aphids, Japanese beetle, slugs. Diseases and disorders: basil downy mildew, fusarium wilt, damping off.
- Harvest (from about Jun 27 – Jul 27). Basil takes 30-60 days to reach harvest. Cold soil stalls it - wait for warm nights. Pinch above a leaf pair every couple of weeks and remove flower buds to keep leaves coming. Downy mildew-resistant varieties are worth seeking out.
Figures come from our crop data; dates use Maine’s average frost dates. More in the full basil growing guide.
Basil planting dates by USDA zone in 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, so the basil dates shift with them.
When to plant basil in nearby states
| State | Last frost | Plant out |
|---|---|---|
| Maine (this page) | May 14 | May 21 – Jun 7 |
| New Hampshire | May 13 | May 20 – Jun 6 |
| Vermont | May 14 | May 21 – Jun 7 |
| Massachusetts | April 24 | May 1 – May 18 |
| Rhode Island | April 25 | May 2 – May 19 |
| Connecticut | April 25 | May 2 – May 19 |
| New York | May 1 | May 8 – May 25 |
Questions gardeners in Maine ask
When is the best time to plant basil in Maine?
Plant basil transplants outdoors in Maine between May 21 and June 7. That timing is set by Maine's average last spring frost of May 14.
When should I start basil seeds indoors in Maine?
Start seeds indoors between April 2 and April 16, about 5 weeks before the last frost, so the seedlings are ready to plant out from May 21.
What is the latest I can plant basil in Maine?
About August 26. Basil needs at least 30 days to mature, and frost around September 25 ends the season, so later plantings risk being cut short.
When will basil planted in Maine be ready to harvest?
Planted on time, basil is usually ready from about June 27 to July 27, 30-60 days after planting.
When is the last frost in Maine?
On average around May 14, with the first fall frost around September 25 - about 134 frost-free days. Your town may differ by two weeks or more.