When to Plant Sunflower in Smyth County, VA
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.
Smyth County, Virginia is in USDA Zone 6b. The average last spring frost is May 2 and the first fall frost is October 12, giving you a growing season of approximately 163 days.
At an elevation of 375 feet, Smyth County receives approximately 51.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Sunflower during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sunflower root diseases.
Smyth County Soil Profile
Soil Type
Silt Loam
Soil pH
5.3-6.8
Drainage
Well Drained
Plant Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Plant Water Budget
Sunflower Planting Timeline — Smyth County, VA
Sunflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 7 | Mar 7 – Mar 21 |
| Transplant Outdoors | May 16 | May 16 – May 30 |
| Direct Sow | May 9 | May 9 – May 30 |
| Harvest | July 25 | Jul 25 – Sep 12 |
Plant 1" deep · 18" apart · Rows 30" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Low — drought tolerant
Days to Maturity
70–100 days
Soil pH
6 – 7.5
USDA Zone
Zone 6b
Growing Season
163 days
Growing Tips for Smyth County
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
Sunflower in Other Locations
Frequently Asked Questions
When should I plant Sunflower in Smyth County, VA?
Smyth County is in Zone 6b with an average last frost of May 2. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Smyth County, VA?
Smyth County, Virginia is in USDA Hardiness Zone 6b. The average last spring frost is May 2 and first fall frost is October 12.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Smyth County gardeners in Zone 6b organize planting dates, track what's growing, and never miss a planting window.
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