When to Plant Sweet Potatoes in Marion County, AL
Sweet potatoes are a warm-season root crop that produces nutritious, sweet tubers in orange, white, and purple varieties. They need a long, hot growing season.
Marion County, Alabama is in USDA Zone 7a. The average last spring frost is March 26 and the first fall frost is November 5, giving you a growing season of approximately 224 days.
At an elevation of 387 feet, Marion County receives approximately 56.4 inches of rainfall annually with predominantly clay loam soil. Summer highs average 93°F, providing good warmth for Sweet Potatoes during the growing season. Clay soil retains moisture well for Sweet Potatoes, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sweet Potatoes root diseases.
Marion County Soil Profile
Soil Type
Clay Loam
Soil pH
5.5-6.8
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
Sweet Potatoes Planting Timeline — Marion County, AL
Sweet Potatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 5 | Feb 5 – Feb 19 |
| Transplant Outdoors | April 9 | Apr 9 – Apr 23 |
| Direct Sow | April 2 | Apr 2 – Apr 23 |
| Harvest | July 9 | Jul 9 – Aug 27 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | — |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | — |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
90–120 days
Soil pH
5.5 – 6.5
USDA Zone
Zone 7a
Growing Season
224 days
Growing Tips for Marion County
Plant slips (rooted sprouts) after soil is thoroughly warm. Build raised mounds for better root development. Cure harvested roots at 80-85F for 10 days to develop sweetness.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Sweet Potatoes in Other Locations
Frequently Asked Questions
When should I plant Sweet Potatoes in Marion County, AL?
Marion County is in Zone 7a with an average last frost of March 26. Plan your Sweet Potatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is Marion County, AL?
Marion County, Alabama is in USDA Hardiness Zone 7a. The average last spring frost is March 26 and first fall frost is November 5.
Plan Your Garden with Confidence
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