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When to Plant Watermelon Radish in Whittier, California (90607)

Location

Whittier, California

ZIP Code

90607

USDA Zone

10b

Last Frost

Thursday, January 15, 2026

📅 Planting Calendar

Direct Sow Outdoors Thursday, December 18, 2025

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 Whittier?

Get your seeds now so they're ready by Thursday, December 18, 2025.

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🤝 Good Companions

CarrotSpinachLettucePea

⚠️ Avoid Planting Near

Hyssop

Other Plants for Whittier

Growing Watermelon Radish in Zone 10b

Watermelon Radish (Raphanus sativus) is a popular garden vegetable. In Whittier, California, which is in USDA Hardiness Zone 10b, you should direct sow seeds around Thursday, December 18, 2025.

Your average last frost date is Thursday, January 15, 2026. Watermelon Radish grows well when direct sown, as it doesn't transplant well or germinates quickly outdoors.