When to Plant Sunflower in USDA Zone 10b
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 10b, the average last spring frost is around January 1 and the first fall frost is around December 31, giving you a growing season of approximately 364 days.
Sunflower Planting Timeline — Zone 10b
Where Is USDA Zone 10b?
The map below highlights the states that contain Zone 10b. Click any state to see the Sunflower planting schedule for that location.
Sunflower Planting Calendar — Zone 10b
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | November 20 | Nov 20 – Dec 4 |
| Transplant Outdoors | January 8 | Jan 8 – Jan 22 |
| Direct Sow | January 1 | Jan 1 – Jan 22 |
| Harvest | March 19 | Mar 19 – May 7 |
Plant 1" deep · 18" apart · Rows 30" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Transplant Outdoors Direct Sow |
| February | — |
| March | Harvest |
| April | Harvest |
| May | Harvest |
| June | — |
| July | — |
| August | — |
| September | — |
| October | — |
| November | Start Indoors |
| December | Start Indoors |
Free Zone 10b Planting Calendar PDF
Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 10b 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
35°F to 40°F average annual minimum
Growing Season
364 days (Zone 10b average)
Planting Specifications
| Planting Depth | 1 inches |
| Plant Spacing | 18 inches apart |
| Row Spacing | 30 inches between rows |
Growing Tips for Zone 10b
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
Reduce heat stress and sun scorch in hot climates with UV-stabilized shade cloth.
Start seeds indoors with reusable cell trays and humidity domes.
Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.
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 10b?
In Zone 10b, plan your Sunflower planting around the average last frost date of January 1. Start seeds indoors around November 20. Direct sow outdoors around January 1. Transplant seedlings around January 8.
Can Sunflower grow in Zone 10b?
Yes, Sunflower can grow well in Zone 10b, hardy in USDA zones 2a through 11b. Zone 10b has a growing season of approximately 364 days, which is sufficient for Sunflower (70-100 days to maturity).
When can I harvest Sunflower in Zone 10b?
In Zone 10b, expect to harvest Sunflower from March 19 – May 7. Sunflower takes 70-100 days from planting to harvest.
What is the last frost date for Zone 10b?
The average last spring frost in Zone 10b is around January 1, and the first fall frost is around December 31. This gives a growing season of approximately 364 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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