When to Plant Potatoes in McMullen County, TX
Potatoes are a versatile staple crop that produces tubers underground. They come in hundreds of varieties with varying colors, textures, and maturity dates.
McMullen County, Texas is in USDA Zone 9a. The average last spring frost is February 20 and the first fall frost is December 1, giving you a growing season of approximately 284 days.
At an elevation of 3,741 feet, McMullen County receives approximately 58 inches of rainfall annually with predominantly loam soil. Summer highs average 103°F, so Potatoes may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Potatoes root diseases.
McMullen County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.2
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 McMullen County
How your county's soil matches Potatoes's growing requirements.
Soil pH
Your soil pH (6.8–7.2) is more alkaline than Potatoes prefers (5.0–6.5). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in McMullen County is excellent for Potatoes — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.3%). Annual compost additions will help Potatoes.
How to Plant Potatoes
Succession Planting Potatoes
Sow every 8 weeks. Last sowing by Aug 03 to harvest before frost.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Potatoes
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 | Potatoes Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.6" | 0" | ❄️ Dormant |
| Feb | 4.3" | 2" | 2.3" | 🚿 Regular watering |
| Mar | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Apr | 4.3" | 6.4" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 9.4" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 9.8" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 7.3" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 6.5" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Nov | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Dec | 4.3" | 1.3" | 3" | 🚿 Regular watering |
Water needs are for active growing months only (Feb–Dec in McMullen County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
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.
Potatoes Planting Timeline — McMullen County, TX
Potatoes Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 9 | Jan 9 – Jan 23 |
| Transplant Outdoors | February 27 | Feb 27 – Mar 13 |
| Direct Sow | February 20 | Feb 20 – Mar 13 |
| Harvest | May 8 | May 8 – Jul 17 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Transplant Outdoors Direct Sow |
| March | Transplant Outdoors Direct Sow |
| April | — |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
70–120 days
🧪 Soil pH
Needs 5–6.5 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 9a
📆 Growing Season
284 days in McMullen County
Growing Tips for Potatoes in McMullen County
Direct sow Potatoes outdoors after February 20 in McMullen County when soil has warmed and frost danger has passed.
With summer highs reaching 103°F in McMullen County, provide afternoon shade for Potatoes and water deeply in the morning.
Common pests for Potatoes in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.
General growing tips
Plant seed potatoes (not grocery store potatoes) 4 inches deep in spring. Hill soil around stems as plants grow to prevent greening. Stop watering when plants die back.
Companion Planting
Good Companions
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Potatoes in Other Locations
Frequently Asked Questions
When should I plant Potatoes in McMullen County, TX?
McMullen County is in Zone 9a with an average last frost of February 20. Plan your Potatoes planting based on this frost date — see the calendar above for exact timing.
What planting zone is McMullen County, TX?
McMullen County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 20 and first fall frost is December 1.
Plan Your Garden with Confidence
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