USDA hardiness zone lookup
Biddeford, ME — USDA Zone 5b
Biddeford, Maine · 142-day growing season
Frost dates and growing season in Biddeford
| USDA hardiness zone | Zone 5b |
|---|---|
| Average last spring frost | May 11 |
| Average first fall frost | September 30 |
| Growing season length | ~142 days |
| Temperature range (F) | -20 to -10°F |
| Temperature range (C) | -29 to -23°C |
All of Biddeford's mapped ZIP codes fall in the same hardiness band, Zone 5b.
These are 50%-probability averages modeled from Biddeford's USDA hardiness zone and regional climate normals — not a single-station reading. In a typical year the last spring frost will have passed by May 11, but a colder-than-average year can run 1-2 weeks later. Plant tender crops (tomatoes, peppers, basil) once both soil and night temperatures are consistently warm — a thermometer beats the calendar.
Growing season in Biddeford
Biddeford, Maine sits in USDA Zone 5b, with roughly 142 frost-free days between an average last spring frost around May 11 and a first fall frost around September 30. That is a standard temperate season — most common vegetables finish comfortably, and a single main planting plus one succession round works well.
What grows in Biddeford
Biddeford falls in USDA Zone 5b, so the same hardiness constraints apply as the full Zone 5 guide. Vegetables, herbs, and fruit trees rated to Zone 5b (or hardier) will overwinter here in a typical year.
- Tomatoes (full range of varieties)
- Peppers
- Eggplant
- Squash, melons, cucumbers
- Beans (bush + pole)
- Sweet corn
- Apples, pears, plums
- Cherries (sweet + sour)
- Blueberries, raspberries
- Garlic
What to plant in Biddeford this week
Biddeford's last frost is around May 11. This is the spring transplant window — start tomatoes and peppers indoors if you haven't, and direct-sow cold-tolerant crops now.
- When to plant tomatoes in zone 5
- When to plant peppers in zone 5
- When to plant basil in zone 5
- When to plant bush beans in zone 5
- When to plant cucumbers in zone 5
Full planting calendar for Biddeford
Crop-by-crop sowing, transplant, and harvest dates calibrated to zone 5 averages:
- When to plant tomatoes in zone 5
- When to plant peppers in zone 5
- When to plant basil in zone 5
- When to plant garlic in zone 5
- When to plant lettuce in zone 5
- When to plant bush beans in zone 5
- When to plant cucumbers in zone 5
- When to plant summer squash in zone 5
- When to plant peas in zone 5
- When to plant carrots in zone 5
ZIP codes in Biddeford
Drill down to the precise frost window and planting calendar for a specific ZIP in Biddeford:
Local microclimate notes
Zone tables give you the average — but Biddefordgardens vary. South-facing walls and paved areas can run a full half-zone warmer than the published rating. Low-lying spots, frost pockets, and shaded north sides can run colder. If you've gardened here a few seasons, your own frost record — the last time you actually got frost damage — beats any national average.
Source and methodology
Hardiness zone from the USDA Plant Hardiness Zone Map (2023 revision). Frost-date and growing-season figures are modeled from Biddeford's USDA hardiness zone and regional NOAA 1991-2020 climate normals — zone-level estimates, not a per-station record, so treat them as planning guidance and confirm against your own local frost history. Crop recommendations draw on US Cooperative Extension references, curated by the Growli editorial team. Last reviewed June 2026.
Other cities in Maine
- Augusta, ME — USDA Zone 5b
- Bangor, ME — USDA Zone 5a
- Lewiston, ME — USDA Zone 5b
- Portland, ME — USDA Zone 6a
- South Portland, ME — USDA Zone 6a
- Waterville, ME — USDA Zone 5a
- All of Maine by zone