When to Plant Sweet Potatoes in Madison County, MS
Your May game plan for Madison County, Mississippi
May is a pivotal month for Madison County, Mississippi gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Start sweet potatoes under lights
These need a head start before your last frost (March 13). Sow into cells now so you're ready to transplant in a few weeks.
Coming up in June — start thinking about
- First harvests: sweet potatoes
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.
Madison County, Mississippi is in USDA Zone 8b. The average last spring frost is March 13 and the first fall frost is November 11, giving you a growing season of approximately 243 days.
At an elevation of 248 feet, Madison County receives approximately 56.7 inches of rainfall annually with predominantly clay loam soil. Summer highs average 97°F, so Sweet Potatoes may need afternoon shade and extra watering during peak heat. 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.
Madison County Soil Profile
Soil Type
Clay Loam
Soil pH
5.7-6.7
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.
Soil Compatibility in Madison County
How your county's soil matches Sweet Potatoes's growing requirements.
Soil pH
Your soil pH (5.7–6.7) overlaps with Sweet Potatoes's range (5.5–6.5), though not a perfect match.
Soil Texture
The clay loam soil in Madison County is excellent for Sweet Potatoes — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.3%). Annual compost additions will help Sweet Potatoes.
How to Plant Sweet Potatoes
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Sweet Potatoes
Sweet Potatoes needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Sweet Potatoes Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 5.4" | 0" | ❄️ Dormant |
| Feb | — | 4.3" | 0" | ❄️ Dormant |
| Mar | 4.3" | 5.3" | 0" | ✅ Rainfall sufficient |
| Apr | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 5.6" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 5.1" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 5.3" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 4.7" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 3.3" | 1" | 💧 Light watering |
| Nov | 4.3" | 4.9" | 0" | ✅ Rainfall sufficient |
| Dec | — | 4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Madison County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Sweet Potatoes Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Sweet Potatoes Planting Timeline — Madison County, MS
Sweet Potatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 23 | Jan 23 – Feb 6 |
| Transplant Outdoors | March 27 | Mar 27 – Apr 10 |
| Direct Sow | March 20 | Mar 20 – Apr 10 |
| Harvest | June 26 | Jun 26 – Aug 14 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Start Indoors |
| March | Transplant Outdoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 5.5–6.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 8b
📆 Growing Season
243 days in Madison County
Growing Tips for Sweet Potatoes in Madison County
Direct sow Sweet Potatoes outdoors after March 13 in Madison County when soil has warmed and frost danger has passed.
With Madison County's clay soil (29% clay), work in 3-4 inches of compost before planting Sweet Potatoes. Avoid tilling when soil is wet to prevent compaction.
With summer highs reaching 97°F in Madison County, provide afternoon shade for Sweet Potatoes and water deeply in the morning.
General growing tips
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
Check more plant combinations with our Companion Planting Checker →
Sweet Potatoes in Other Locations
Frequently Asked Questions
When should I plant Sweet Potatoes in Madison County, MS?
Madison County is in Zone 8b with an average last frost of March 13. Plan your Sweet Potatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is Madison County, MS?
Madison County, Mississippi is in USDA Hardiness Zone 8b. The average last spring frost is March 13 and first fall frost is November 11.
Your Madison County Garden Planner — Free
A 24-page printable planner built for Madison County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.