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When to Plant Watermelon Radish in Haiku, Hawaii (96708)

Location

Haiku, Hawaii

ZIP Code

96708

USDA Zone

12a

Last Frost

Thursday, January 1, 2026

📅 Planting Calendar

Direct Sow Outdoors Thursday, December 4, 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 Haiku?

Get your seeds now so they're ready by Thursday, December 4, 2025.

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🤝 Good Companions

CarrotSpinachLettucePea

⚠️ Avoid Planting Near

Hyssop

Other Plants for Haiku

Growing Watermelon Radish in Zone 12a

Watermelon Radish (Raphanus sativus) is a popular garden vegetable. In Haiku, Hawaii, which is in USDA Hardiness Zone 12a, you should direct sow seeds around Thursday, December 4, 2025.

Your average last frost date is Thursday, January 1, 2026. Watermelon Radish grows well when direct sown, as it doesn't transplant well or germinates quickly outdoors.