When to Plant Sunflower in USDA Zone 8b
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 8b, the average last spring frost is around February 25 and the first fall frost is around November 28, giving you a growing season of approximately 276 days.
Sunflower Planting Timeline — Zone 8b
Where Is USDA Zone 8b?
The map below highlights the states that contain Zone 8b. Click any state to see the Sunflower planting schedule for that location.
Sunflower Planting Calendar — Zone 8b
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 7 | Jan 7 – Jan 21 |
| Transplant Outdoors | March 11 | Mar 11 – Mar 25 |
| Direct Sow | March 4 | Mar 4 – Mar 25 |
| Harvest | May 20 | May 20 – Jul 8 |
Plant 1" deep · 18" apart · Rows 30" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | — |
| March | Transplant Outdoors Direct Sow |
| April | — |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Free Zone 8b Planting Calendar PDF
Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 8b 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
15°F to 20°F average annual minimum
Growing Season
276 days (Zone 8b average)
Planting Specifications
| Planting Depth | 1 inches |
| Plant Spacing | 18 inches apart |
| Row Spacing | 30 inches between rows |
Growing Tips for Zone 8b
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
- Alberta
- Arizona
- Arkansas
- British Columbia
- California
- Colorado
- Connecticut
- Delaware
- Florida
- Georgia
- Hawaii
- Idaho
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Louisiana
- Maine
- Manitoba
- Maryland
- Massachusetts
- Michigan
- Minnesota
- Mississippi
- Missouri
- Montana
- Nebraska
- Nevada
- New Brunswick
- New Hampshire
- New Jersey
- New Mexico
- New York
- Newfoundland and Labrador
- North Carolina
- North Dakota
- Northwest Territories
- Nova Scotia
- Nunavut
- Ohio
- Oklahoma
- Ontario
- Oregon
- Pennsylvania
- Prince Edward Island
- Quebec
- Rhode Island
- Saskatchewan
- South Carolina
- South Dakota
- Tennessee
- Texas
- Utah
- Vermont
- Virginia
- Washington
- West Virginia
- Wisconsin
- Wyoming
- Yukon
Frequently Asked Questions
When should I plant Sunflower in Zone 8b?
In Zone 8b, plan your Sunflower planting around the average last frost date of February 25. Start seeds indoors around January 7. Direct sow outdoors around March 4. Transplant seedlings around March 11.
Can Sunflower grow in Zone 8b?
Yes, Sunflower can grow well in Zone 8b, hardy in USDA zones 2a through 11b. Zone 8b has a growing season of approximately 276 days, which is sufficient for Sunflower (70-100 days to maturity).
When can I harvest Sunflower in Zone 8b?
In Zone 8b, expect to harvest Sunflower from May 20 – July 8. Sunflower takes 70-100 days from planting to harvest.
What is the last frost date for Zone 8b?
The average last spring frost in Zone 8b is around February 25, and the first fall frost is around November 28. This gives a growing season of approximately 276 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
Get our free Garden Planner — organize your planting dates for Zone 8b, track your crops, and plan your garden season from seed to harvest.
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