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When to Plant Sunflower in Jackson County, TN

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.

Jackson County, Tennessee is in USDA Zone 6b. The average last spring frost is April 10 and the first fall frost is October 25, giving you a growing season of approximately 198 days.

At an elevation of 1,976 feet, Jackson County receives approximately 51.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87ยฐF, providing good warmth for Sunflower during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sunflower root diseases.

Jackson County, TN (Zone 6b) Moderate season
198 days
Last Spring Frost April 10
198 growing days
First Fall Frost October 25

Jackson County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (65 days to spare)
Start indoors: Feb 9 Transplant: Apr 20 🍅 Harvest: Jun 29 – Aug 17
Recommended (50%) ✓ Fits season (65 days to spare)
Start indoors: Feb 13 Transplant: Apr 24 🍅 Harvest: Jul 3 – Aug 21
Safe Start (90%) ✓ Fits season (71 days to spare)
Start indoors: Feb 26 Transplant: May 7 🍅 Harvest: Jul 16 – Sep 3

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.

Soil Compatibility in Jackson County

How your county's soil matches Sunflower's growing requirements.

Soil pH

Your soil pH (5.5โ€“7.0) overlaps with Sunflower's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

The silt loam soil in Jackson County is excellent for Sunflower โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.0%). Annual compost additions will help Sunflower.

How to Plant Sunflower

1"
Planting Depth
18"
Between Plants
30"
Between Rows

Succession Planting Sunflower

3
successive plantings in your 198-day season

Sow every 8 weeks. Last sowing by Jul 17 to harvest before frost.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Sunflower needs ~1,296 GDD — county provides 3,019 GDD Excellent fit

Sunflower Planting Timeline โ€” Jackson County, TN

Sunflower Planting Calendar

Activity When Date Range
Start Indoors February 13 Feb 13 โ€“ Feb 27
Transplant Outdoors April 24 Apr 24 โ€“ May 8
Direct Sow April 17 Apr 17 โ€“ May 8
Harvest July 3 Jul 3 โ€“ Aug 21

Plant 1" deep ยท 18" apart ยท Rows 30" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February Start Indoors
March โ€”
April Transplant Outdoors Direct Sow
May Transplant Outdoors Direct Sow
June โ€”
July Harvest
August Harvest
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.5"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

70โ€“100 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 6b

๐Ÿ“† Growing Season

198 days in Jackson County

Growing Tips for Sunflower in Jackson County

Direct sow Sunflower outdoors after April 10 in Jackson County when soil has warmed and frost danger has passed.

Common pests for Sunflower in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

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

  • Potatoes

Level Up Your Garden

Frequently Asked Questions

When should I plant Sunflower in Jackson County, TN?

Jackson County is in Zone 6b with an average last frost of April 10. Plan your Sunflower planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Jackson County, TN?

Jackson County, Tennessee is in USDA Hardiness Zone 6b. The average last spring frost is April 10 and first fall frost is October 25.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Jackson County gardeners in Zone 6b organize planting dates, track what's growing, and never miss a planting window.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Jackson County, TN. Local conditions may vary. Last updated: April 2026.