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When to Plant Sweet Pea in Box Elder, Montana (59521)

Location

Box Elder, Montana

ZIP Code

59521

USDA Zone

4a

Last Frost

Friday, May 15, 2026

📅 Planting Calendar

Direct Sow Outdoors Friday, April 17, 2026

Pro Tip: Sow Sweet Pea directly outdoors 4 weeks before your last frost date.

🌿 Plant Details

Scientific Name Lathyrus odoratus
Days to Maturity 65 days
Mature Height 48-72"
Spread 8"

☀️ Growing Requirements

☀️

Sun

Full Sun (6-8 hours)

💧

Water

Regular (1-2 inches/week)

↔️

Spacing

6" apart

🌱

Planting Depth

1" deep

Seeds typically germinate in 10-21 days

Ready to Plant Sweet Pea in Box Elder?

Get your seeds now so they're ready by Friday, April 17, 2026.

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🤝 Good Companions

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⚠️ Avoid Planting Near

OnionGarlic

Other Plants for Box Elder

Growing Sweet Pea in Zone 4a

Sweet Pea (Lathyrus odoratus) is a popular garden vegetable. In Box Elder, Montana, which is in USDA Hardiness Zone 4a, you should direct sow seeds around Friday, April 17, 2026.

Your average last frost date is Friday, May 15, 2026. Sweet Pea grows well when direct sown, as it doesn't transplant well or germinates quickly outdoors.