When to Plant Hollyhock in Saint Petersburg, Florida (33708)

Location

Saint Petersburg, Florida

ZIP Code

33708

USDA Zone

10b

Last Frost

Thursday, January 15, 2026

📅 Your 2026 Planting Dates

Start Seeds Indoors

Thursday, December 4, 2025

Transplant Outdoors

Thursday, January 29, 2026

Based on last frost Thursday, January 15, 2026 · Zone 10b

Pro tip: Start Hollyhock seeds indoors 6 weeks before your last frost date, then transplant outdoors around Thursday, January 29, 2026.

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🌿 Plant Details

Scientific Name Alcea rosea

Days to Maturity 365 days

Mature Height 48-96"

Spread 24"

☀️ Growing Requirements

☀️

Sun

Full Sun (6-8 hours)

💧

Water

Moderate (1 inch/week)

↔️

Spacing

18" apart

🌱

Planting Depth

0.25" deep

Seeds typically germinate in 10-14 days

Ready to Plant Hollyhock in Saint Petersburg?

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

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🤝 Good Companions

RoseVegetable Garden

🤝

Full Companion Planting Guide for Hollyhock

See which plants help Hollyhock thrive, which to keep away, and raised bed layout tips →

🛠️ Supplies You'll Need

🌱 Seed Starting Trays 🪴 Seed Starting Mix 💡 Grow Lights 🌡️ Heat Mat 🌍 Flower Garden Soil ✂️ Pruning Shears 🚿 Watering Can

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🌾 Seed Saving Guide

🟢 Easy

✅ Open-pollinated — seeds grow true to parent

When to Harvest Seed

Allow seed pods (disc-shaped) to dry on the stalk after petals drop. Harvest when brown and papery.

Processing

Remove seeds from papery rings, spread to dry 1 week before storing.

Seed Viability

Up to 2 years when stored cool, dark, and dry.

Pro Tip

Hollyhocks cross freely with other hollyhock varieties. Expect some color variation in seed-grown plants.

🪴

Raised Bed Planting Guides

A 4×8 bed fits 14 plants of Hollyhock. See plant counts, spacing grids, and companion pairings for every bed size →

Frequently Asked Questions

When should I plant Hollyhock in Saint Petersburg, Florida? +

In Saint Petersburg (Zone 10b), start Hollyhock seeds indoors around Thursday, December 4, 2025 and transplant outdoors around Thursday, January 29, 2026.

What is the last frost date for Saint Petersburg, Florida? +

The average last spring frost date for Saint Petersburg, Florida (ZIP 33708) is around Thursday, January 15, 2026. This is based on NOAA climate normals for USDA Zone 10b.

How long does Hollyhock take to grow? +

Hollyhock typically matures in about 365 days from transplanting. In Saint Petersburg, that means you can expect harvest around Thursday, January 29, 2026 plus 365 days.

Should I start Hollyhock indoors or direct sow in Florida? +

Hollyhock should be started indoors 6 weeks before your last frost date. In Saint Petersburg, that means starting around Thursday, December 4, 2025.

📚 More Hollyhock Planting Guides

🗺️

Hollyhock in Florida

Zone-by-zone breakdown · Full state guide

→ 🌡️

Zone 10b Hollyhock Guide

All cities in your zone · Avg dates

→

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Growing Hollyhock in Zone 10b

Hollyhock (Alcea rosea) is a popular garden vegetable. In Saint Petersburg, Florida, which is in USDA Hardiness Zone 10b, you should start seeds indoors around Thursday, December 4, 2025.

Your average last frost date is Thursday, January 15, 2026. Plan to transplant your Hollyhock seedlings outdoors around Thursday, January 29, 2026, about 2 weeks after your last frost date.