When to Plant Cosmos in Saint Lucas, Iowa (52166)

Location

Saint Lucas, Iowa

ZIP Code

52166

USDA Zone

Last Frost

Sunday, May 10, 2026

📅 Planting Calendar

Direct Sow Outdoors Sunday, May 10, 2026

Pro Tip: Sow Cosmos directly outdoors around your last frost date when soil starts to warm.

🌿 Plant Details

Scientific Name Cosmos bipinnatus

Days to Maturity 60 days

Mature Height 24-60"

Spread 18"

Type Annual

☀️ Growing Requirements

☀️

Sun

Full Sun (6-8 hours)

💧

Water

Low-Moderate

↔️

Spacing

18" apart

🌱

Planting Depth

0.25" deep

Seeds typically germinate in 7-14 days

Ready to Plant Cosmos in Saint Lucas?

Get your seeds now so they're ready by Sunday, May 10, 2026.

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Other Plants for Saint Lucas

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Growing Cosmos in Zone 5a

Cosmos (Cosmos bipinnatus) is a popular garden vegetable. In Saint Lucas, Iowa, which is in USDA Hardiness Zone 5a, you should direct sow seeds around Sunday, May 10, 2026.

Your average last frost date is Sunday, May 10, 2026. Cosmos grows well when direct sown, as it doesn't transplant well or germinates quickly outdoors.