When to Plant Mustard in Honolulu, Hawaii (96821)
Location
Honolulu, Hawaii
ZIP Code
96821
USDA Zone
12b
Last Frost
Thursday, January 1, 2026
📅 Planting Calendar
Direct Sow Outdoors Thursday, November 20, 2025
Pro Tip: Sow Mustard directly outdoors 6 weeks before your last frost date.
🌿 Plant Details
Scientific Name Brassica juncea
Days to Maturity 56 days
☀️ Growing Requirements
☀️
Sun
Full Sun
💧
Water
Regular
Seeds typically germinate in 1-7 days
Ready to Plant Mustard in Honolulu?
Get your seeds now so they're ready by Thursday, November 20, 2025.
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Growing Mustard in Zone 12b
Mustard (Brassica juncea) is a popular garden vegetable. In Honolulu, Hawaii, which is in USDA Hardiness Zone 12b, you should direct sow seeds around Thursday, November 20, 2025.
Your average last frost date is Thursday, January 1, 2026. Mustard grows well when direct sown, as it doesn't transplant well or germinates quickly outdoors.