When to Plant Sweet Potatoes in Posey County, IN
Your May planting checklist for Posey County, Indiana
Each item below is timed to Posey County, Indiana's frost dates and soil temperatures. Skip nothing, stress about nothing.
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Begin indoor sowing: sweet potatoes
Starting these indoors now means sturdy transplants ready the moment your soil warms up.
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.
Posey County, Indiana is in USDA Zone 7a. The average last spring frost is April 8 and the first fall frost is October 28, giving you a growing season of approximately 203 days.
At an elevation of 596 feet, Posey County receives approximately 40.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Sweet Potatoes during the growing season.
Posey County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-7
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 Posey County
How your county's soil matches Sweet Potatoes's growing requirements.
Soil pH
Your soil pH (6.2–7.0) is more alkaline than Sweet Potatoes prefers (5.5–6.5). Add sulfur or peat moss to lower pH.
Soil Texture
The silt loam soil in Posey County is excellent for Sweet Potatoes — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.9%). 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 | — | 1.8" | 0" | ❄️ Dormant |
| Feb | — | 1.9" | 0" | ❄️ Dormant |
| Mar | — | 2.7" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| May | 4.3" | 5.2" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 4.7" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 3" | 1.3" | 💧 Light watering |
| Oct | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Nov | — | 2.7" | 0" | ❄️ Dormant |
| Dec | — | 2.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Posey 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 — Posey County, IN
Sweet Potatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 18 | Feb 18 – Mar 4 |
| Transplant Outdoors | April 22 | Apr 22 – May 6 |
| Direct Sow | April 15 | Apr 15 – May 6 |
| Harvest | July 22 | Jul 22 – Sep 9 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| 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: too_alkaline
🗺️ USDA Zone
Zone 7a
📆 Growing Season
203 days in Posey County
Growing Tips for Sweet Potatoes in Posey County
Direct sow Sweet Potatoes outdoors after April 08 in Posey 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 Posey County, IN?
Posey County is in Zone 7a with an average last frost of April 8. Plan your Sweet Potatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is Posey County, IN?
Posey County, Indiana is in USDA Hardiness Zone 7a. The average last spring frost is April 8 and first fall frost is October 28.
Your Posey County Garden Planner — Free
A 24-page printable planner built for Posey County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.