When to Plant Onion in West Boothbay Harbor, Maine (04575)

Location

West Boothbay Harbor, Maine

ZIP Code

04575

USDA Zone

Last Frost

Monday, April 20, 2026

📅 Planting Calendar

Start Seeds Indoors Monday, February 23, 2026

Transplant Outdoors Monday, May 4, 2026

Pro Tip: Start Onion seeds indoors 8 weeks before your last frost date, then transplant outdoors around Monday, May 4, 2026.

🌿 Plant Details

Scientific Name Allium cepa

Days to Maturity 100 days

Mature Height 12-18"

Spread 4"

Type Bulb

Fruit Size Medium (2-4 inch bulb)

☀️ Growing Requirements

☀️

Sun

Full Sun (6+ hours)

💧

Water

Moderate

↔️

Spacing

4" apart

🌱

Planting Depth

0.5" deep

Seeds typically germinate in 7-10 days

Ready to Plant Onion in West Boothbay Harbor?

Get your seeds now so they're ready by Monday, February 23, 2026.

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🤝 Good Companions

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⚠️ Avoid Planting Near

BeanPeaAsparagus

Other Plants for West Boothbay Harbor

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Growing Onion in Zone 6a

Onion (Allium cepa) is a popular garden vegetable. In West Boothbay Harbor, Maine, which is in USDA Hardiness Zone 6a, you should start seeds indoors around Monday, February 23, 2026.

Your average last frost date is Monday, April 20, 2026. Plan to transplant your Onion seedlings outdoors around Monday, May 4, 2026, about 2 weeks after your last frost date.