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When to Plant Hollyhock in Honolulu, Hawaii (96821)

Location

Honolulu, Hawaii

ZIP Code

96821

USDA Zone

12b

Last Frost

Thursday, January 1, 2026

๐Ÿ“… Planting Calendar

Start Seeds Indoors Thursday, November 20, 2025
Transplant Outdoors Thursday, January 15, 2026

Pro Tip: Start Hollyhock seeds indoors 6 weeks before your last frost date, then transplant outdoors around Thursday, January 15, 2026.

๐ŸŒฟ Plant Details

Scientific Name Alcea rosea
Days to Maturity 365 days
Mature Height 48-96"
Spread 24"

โ˜€๏ธ Growing Requirements

โ˜€๏ธ

Sun

Full Sun (6-8 hours)

๐Ÿ’ง

Water

Moderate (1 inch/week)

โ†”๏ธ

Spacing

18" apart

๐ŸŒฑ

Planting Depth

0.25" deep

Seeds typically germinate in 10-14 days

Ready to Plant Hollyhock in Honolulu?

Get your seeds now so they're ready by Thursday, November 20, 2025.

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Other Plants for Honolulu

Growing Hollyhock in Zone 12b

Hollyhock (Alcea rosea) is a popular garden vegetable. In Honolulu, Hawaii, which is in USDA Hardiness Zone 12b, you should start seeds indoors around Thursday, November 20, 2025.

Your average last frost date is Thursday, January 1, 2026. Plan to transplant your Hollyhock seedlings outdoors around Thursday, January 15, 2026, about 2 weeks after your last frost date.