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When to Plant Watermelon Radish in Cable, Wisconsin (54821)

Location

Cable, Wisconsin

ZIP Code

54821

USDA Zone

4a

Last Frost

Friday, May 15, 2026

📅 Planting Calendar

Direct Sow Outdoors Friday, April 17, 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 Cable?

Get your seeds now so they're ready by Friday, April 17, 2026.

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🤝 Good Companions

CarrotSpinachLettucePea

⚠️ Avoid Planting Near

Hyssop

Other Plants for Cable

Growing Watermelon Radish in Zone 4a

Watermelon Radish (Raphanus sativus) is a popular garden vegetable. In Cable, Wisconsin, which is in USDA Hardiness Zone 4a, you should direct sow seeds around Friday, April 17, 2026.

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