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When to Plant Sweet Potatoes in Guadalupe 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.

Guadalupe County, Texas is in USDA Zone 8b. The average last spring frost is March 7 and the first fall frost is November 21, giving you a growing season of approximately 259 days.

At an elevation of 3,679 feet, Guadalupe County receives approximately 63 inches of rainfall annually with predominantly clay soil. Summer highs average 93ยฐF, 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.

Guadalupe County, TX (Zone 8b) Long season
259 days
Last Spring Frost March 7
259 growing days
First Fall Frost November 21

Guadalupe County Soil Profile

Soil Type

Clay

Soil pH

6.9-8.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (105 days to spare)
Start indoors: Jan 9 Transplant: Mar 13 🍅 Harvest: Jun 12 – Jul 31
Recommended (50%) ✓ Fits season (105 days to spare)
Start indoors: Jan 17 Transplant: Mar 21 🍅 Harvest: Jun 20 – Aug 8
Safe Start (90%) ✓ Fits season (95 days to spare)
Start indoors: Feb 16 Transplant: Apr 20 🍅 Harvest: Jul 20 – Sep 7

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 Guadalupe County

How your county's soil matches Sweet Potatoes's growing requirements.

Soil pH

Your soil pH (6.9โ€“8.2) is more alkaline than Sweet Potatoes prefers (5.5โ€“6.5). Add sulfur or peat moss to lower pH.

Soil Texture

Your clay soil in Guadalupe County is workable for Sweet Potatoes. Add compost annually to improve structure.

Organic Matter

Organic matter is moderate (2.7%). Annual compost additions will help Sweet Potatoes.

How to Plant Sweet Potatoes

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” 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 โ€” 1.6" 0" โ„๏ธ Dormant
Feb โ€” 2.1" 0" โ„๏ธ Dormant
Mar 4.3" 4.4" 0" โœ… Rainfall sufficient
Apr 4.3" 6.5" 0" โœ… Rainfall sufficient
May 4.3" 9.5" 0" โœ… Rainfall sufficient
Jun 4.3" 9.3" 0" โœ… Rainfall sufficient
Jul 4.3" 8" 0" โœ… Rainfall sufficient
Aug 4.3" 7.1" 0" โœ… Rainfall sufficient
Sep 4.3" 6.4" 0" โœ… Rainfall sufficient
Oct 4.3" 4.5" 0" โœ… Rainfall sufficient
Nov 4.3" 1.9" 2.4" ๐Ÿšฟ Regular watering
Dec โ€” 1.6" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Guadalupe County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 needs ~2,074 GDD — county provides 5,115 GDD Excellent fit

Sweet Potatoes Planting Timeline โ€” Guadalupe County, TX

Sweet Potatoes Planting Calendar

Activity When Date Range
Start Indoors January 17 Jan 17 โ€“ Jan 31
Transplant Outdoors March 21 Mar 21 โ€“ Apr 4
Direct Sow March 14 Mar 14 โ€“ Apr 4
Harvest June 20 Jun 20 โ€“ Aug 8

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

MonthActivities
January Start Indoors
February โ€”
March Transplant Outdoors Direct Sow
April Transplant Outdoors Direct Sow
May โ€”
June Harvest
July Harvest
August Harvest
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

90โ€“120 days

๐Ÿงช Soil pH

Needs 5.5โ€“6.5 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 8b

๐Ÿ“† Growing Season

259 days in Guadalupe County

Growing Tips for Sweet Potatoes in Guadalupe County

Direct sow Sweet Potatoes outdoors after March 07 in Guadalupe County when soil has warmed and frost danger has passed.

With Guadalupe County's clay soil (40% clay), work in 3-4 inches of compost before planting Sweet Potatoes. Avoid tilling when soil is wet to prevent compaction.

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

  • Squash Summer

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sweet Potatoes in Guadalupe County, TX?

Guadalupe County is in Zone 8b with an average last frost of March 7. Plan your Sweet Potatoes planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Guadalupe County, TX?

Guadalupe County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 7 and first fall frost is November 21.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Guadalupe County gardeners in Zone 8b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Guadalupe County, TX. Local conditions may vary. Last updated: April 2026.