Sunflower illustration 🌻

🌻 Growing Sunflower in Zone 11b

Zone 11b has a year-round growing season. Sunflower can be planted almost any time with proper planning. Last frost: Jan 15. First frost: Dec 31.

Planting Calendar

Indoor
Outdoor
Harvest
Dec 25Dec 31

Season: Jan 15 – Dec 31 (350 days) · Succession: plant every 2 weeks (up to 18x)

Zone11b
Last FrostJan 15
First FrostDec 31
Season Length350 days
Days to Harvest90
SunFull Sun
Frost ToleranceNone
Spacing1/sqft (12" apart)

When to Plant Sunflower in Zone 11b

Start Seeds Indoors: Dec 25

Start Sunflower seeds indoors around Dec 25 (3 weeks before last frost). Optimal germination temperature: 75°F. Germinates in 7–14 days.

Transplant Outdoors: Jan 22

Transplant Sunflower seedlings outdoors after Jan 22. Wait until soil temperature reaches 55°F. Space plants at 1/sqft (12" apart). Harden off plants for a week before moving outside.

Harvest: Mar 28

First harvest approximately Mar 28 (~65 days from transplant). Continue harvesting until first frost (Dec 31).

Companion Planting

✅ Cucumbers✅ Squash✅ Corn✅ Beans
❌ Potatoes

Frequently Asked Questions

When should I plant Sunflower in Zone 11b?

Start Sunflower seeds indoors around Dec 25. Transplant outdoors after Jan 22. Expect first harvest around Mar 28.

What is the last frost date for Zone 11b?

The average last spring frost date for Zone 11b is Jan 15. The first fall frost averages Dec 31, giving a 350-day growing season.

Can I grow Sunflower in Zone 11b?

Yes. Sunflower needs 90 days to harvest. Zone 11b has a 350-day growing season, which is sufficient. You can plant up to 18 successions.

What is the best month to plant Sunflower in Zone 11b?

The best time to start Sunflower in Zone 11b is Dec. Begin seeds indoors around Dec 25, then transplant outdoors after the last frost date of Jan 15.

What companion plants grow well with Sunflower?

Good companion plants for Sunflower include Cucumbers, Squash, Corn, Beans. Avoid planting Sunflower near Potatoes.

How long does Sunflower take to harvest?

Sunflower takes approximately 90 days from planting to harvest. In Zone 11b, expect your first harvest around Mar 28.

Plan Your Sunflower Garden

Track Sunflower from seed to harvest with personalized frost dates, watering recommendations, and companion planting visualization.

Start Free Sunflower Growing Guide