Sunflower illustration 🌻

🌻 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

Frequently Asked Questions

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.

What is the best month to plant Sunflower in Zone 6b?

The best time to start Sunflower in Zone 6b is Mar. Begin seeds indoors around Mar 25, then transplant outdoors after the last frost date of Apr 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 6b, expect your first harvest around Jun 26.

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