When to Plant Sunflower in USDA Zone 6b
Sunflowers are tall, cheerful annuals grown for their edible seeds and as pollinator magnets. They come in sizes from 2-foot dwarfs to 12-foot giants.
In Zone 6b, the average last spring frost is around April 3 and the first fall frost is around October 25, giving you a growing season of approximately 205 days.
Sunflower Planting Timeline — Zone 6b
Where Is USDA Zone 6b?
The map below highlights the states that contain Zone 6b. Click any state to see the Sunflower planting schedule for that location.
Sunflower Planting Calendar — Zone 6b
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 6 | Feb 6 – Feb 20 |
| Transplant Outdoors | April 17 | Apr 17 – May 1 |
| Direct Sow | April 10 | Apr 10 – May 1 |
| Harvest | June 26 | Jun 26 – Aug 14 |
Plant 1" deep · 18" apart · Rows 30" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | — |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Free Zone 6b Planting Calendar PDF
Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 6b with start dates, transplant windows, and harvest times.
Growing Conditions
Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
Days to Maturity
70–100 days
Soil pH
6 – 7.5
Zone Temperature Range
-5°F to 0°F average annual minimum
Growing Season
205 days (Zone 6b average)
Planting Specifications
| Planting Depth | 1 inches |
| Plant Spacing | 18 inches apart |
| Row Spacing | 30 inches between rows |
Succession Planting Sunflower in Zone 6b
Sow every 8 weeks for continuous harvest throughout the season.
Growing Tips for Sunflower in Zone 6b
Direct sow after last frost. Stake tall varieties in windy areas. Harvest seed heads when the back turns brown and seeds are plump. Dry heads upside down.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Saving Sunflower Seeds
Recommended for Your Garden
Start seeds indoors with reusable cell trays and humidity domes.
Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.
Keep your garden organized with durable, weather-resistant plant labels.
Related Plants
Sunflower in Other Zones
Sunflower by State
- Alabama
- Alaska
- Arizona
- Arkansas
- California
- Colorado
- Connecticut
- Delaware
- Florida
- Georgia
- Hawaii
- Idaho
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Louisiana
- Maine
- Maryland
- Massachusetts
- Michigan
- Minnesota
- Mississippi
- Missouri
- Montana
- Nebraska
- Nevada
- New Hampshire
- New Jersey
- New Mexico
- New York
- North Carolina
- North Dakota
- Ohio
- Oklahoma
- Oregon
- Pennsylvania
- Rhode Island
- South Carolina
- South Dakota
- Tennessee
- Texas
- Utah
- Vermont
- Virginia
- Washington
- West Virginia
- Wisconsin
- Wyoming
Frequently Asked Questions
When should I plant Sunflower in Zone 6b?
In Zone 6b, plan your Sunflower planting around the average last frost date of April 3. Start seeds indoors around February 6. Direct sow outdoors around April 10. Transplant seedlings around April 17.
Can Sunflower grow in Zone 6b?
Yes, Sunflower can grow well in Zone 6b, hardy in USDA zones 2a through 11b. Zone 6b has a growing season of approximately 205 days, which is sufficient for Sunflower (70-100 days to maturity).
When can I harvest Sunflower in Zone 6b?
In Zone 6b, expect to harvest Sunflower from June 26 – August 14. Sunflower takes 70-100 days from planting to harvest.
What is the last frost date for Zone 6b?
The average last spring frost in Zone 6b is around April 3, and the first fall frost is around October 25. This gives a growing season of approximately 205 days. These are 50% probability dates — actual frost dates vary year to year.
What should I plant next to Sunflower?
Good companion plants for Sunflower include Corn, Cucumber, Squash Summer. These companions can help with pest control, pollination, and nutrient sharing.
Plan Your Garden with Confidence
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