When should I plant Sunflower in Zone 6b?

Start Sunflower seeds indoors around Mar 25. Transplant outdoors after Apr 22. Expect first harvest around Jun 26.

What is the last frost date for Zone 6b?

The average last spring frost date for Zone 6b is Apr 15. The first fall frost averages Oct 22, giving a 190-day growing season.

Can I grow Sunflower in Zone 6b?

Yes. Sunflower needs 90 days to harvest. Zone 6b has a 190-day growing season, which is sufficient. You can plant up to 7 successions.

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🌻 Growing Sunflower in Zone 6b

Zone 6b has mild winters and a long growing season — good conditions for Sunflower. Last frost: Apr 15. First frost: Oct 22.

Planting Calendar

Indoor

Outdoor

Harvest

Mar 25Oct 22

Season: Apr 15 – Oct 22 (190 days) · Succession: plant every 2 weeks (up to 7x)

Zone6b

Last FrostApr 15

First FrostOct 22

Season Length190 days

Days to Harvest90

SunFull Sun

Frost ToleranceNone

Spacing1/sqft (12" apart)

When to Plant Sunflower in Zone 6b

Start Seeds Indoors: Mar 25

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

Transplant Outdoors: Apr 22

Transplant Sunflower seedlings outdoors after Apr 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: Jun 26

First harvest approximately Jun 26 (~65 days from transplant). Continue harvesting until first frost (Oct 22).

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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