When to Plant Cosmos in Spokane, Washington (99208)

Location

Spokane, Washington

ZIP Code

99208

USDA Zone

Last Frost

Wednesday, April 15, 2026

📅 Planting Calendar

Direct Sow Outdoors Wednesday, April 15, 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 Spokane?

Get your seeds now so they're ready by Wednesday, April 15, 2026.

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Other Plants for Spokane

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Growing Cosmos in Zone 6b

Cosmos (Cosmos bipinnatus) is a popular garden vegetable. In Spokane, Washington, which is in USDA Hardiness Zone 6b, you should direct sow seeds around Wednesday, April 15, 2026.

Your average last frost date is Wednesday, April 15, 2026. Cosmos grows well when direct sown, as it doesn't transplant well or germinates quickly outdoors.