When to Plant Sweet Potatoes in Fannin County, TX
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.
Fannin County, Texas is in USDA Zone 7b. The average last spring frost is March 16 and the first fall frost is November 15, giving you a growing season of approximately 244 days.
At an elevation of 282 feet, Fannin County receives approximately 63.8 inches of rainfall annually with predominantly loam soil. Summer highs average 88°F, providing good warmth for Sweet Potatoes during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sweet Potatoes root diseases.
Fannin County Soil Profile
Soil Type
Loam
Soil pH
6.3-7.8
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.
Soil Compatibility in Fannin County
How your county's soil matches Sweet Potatoes's growing requirements.
Soil pH
Your soil pH (6.3–7.8) is more alkaline than Sweet Potatoes prefers (5.5–6.5). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Fannin County is excellent for Sweet Potatoes — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.2%). Annual compost additions will help Sweet Potatoes.
How to Plant Sweet Potatoes
Plant Water Budget
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 | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.9" | 0" | ❄️ Dormant |
| Mar | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Apr | 4.3" | 6.3" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 8.7" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 11.1" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 7.7" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 7.9" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 6.2" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Nov | 4.3" | 2.1" | 2.2" | 🚿 Regular watering |
| Dec | — | 1.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Fannin 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 — Fannin County, TX
Sweet Potatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 26 | Jan 26 – Feb 9 |
| Transplant Outdoors | March 30 | Mar 30 – Apr 13 |
| Direct Sow | March 23 | Mar 23 – Apr 13 |
| Harvest | June 29 | Jun 29 – Aug 17 |
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 · Natural rainfall sufficient
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 5.5–6.5 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 7b
📆 Growing Season
244 days in Fannin County
Growing Tips for Sweet Potatoes in Fannin County
Direct sow Sweet Potatoes outdoors after March 16 in Fannin County when soil has warmed and frost danger has passed.
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 Fannin County, TX?
Fannin County is in Zone 7b with an average last frost of March 16. Plan your Sweet Potatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is Fannin County, TX?
Fannin County, Texas is in USDA Hardiness Zone 7b. The average last spring frost is March 16 and first fall frost is November 15.
Plan Your Garden with Confidence
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