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When to Plant Watermelon Radish in Colorado Springs, Colorado (80921)

Location

Colorado Springs, Colorado

ZIP Code

80921

USDA Zone

5b

Last Frost

Saturday, April 25, 2026

📅 Planting Calendar

Direct Sow Outdoors Saturday, March 28, 2026

Pro Tip: Sow Watermelon Radish directly outdoors 4 weeks before your last frost date.

🌿 Plant Details

Scientific Name Raphanus sativus
Days to Maturity 60 days
Mature Height 6-10"
Spread 4"

☀️ Growing Requirements

☀️

Sun

Full Sun (6-8 hours)

💧

Water

Regular (1-2 inches/week)

↔️

Spacing

4" apart

🌱

Planting Depth

0.5" deep

Seeds typically germinate in 3-7 days

Ready to Plant Watermelon Radish in Colorado Springs?

Get your seeds now so they're ready by Saturday, March 28, 2026.

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🤝 Good Companions

CarrotSpinachLettucePea

⚠️ Avoid Planting Near

Hyssop

Other Plants for Colorado Springs

Growing Watermelon Radish in Zone 5b

Watermelon Radish (Raphanus sativus) is a popular garden vegetable. In Colorado Springs, Colorado, which is in USDA Hardiness Zone 5b, you should direct sow seeds around Saturday, March 28, 2026.

Your average last frost date is Saturday, April 25, 2026. Watermelon Radish grows well when direct sown, as it doesn't transplant well or germinates quickly outdoors.