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.

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🌻 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

Sunflower in Other Zones

1a 1b 2a 2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b 11a 11b 12a 12b 13a 13b

Plan Your Sunflower Garden

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

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