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When to Plant Sweet Potatoes in Lavaca 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.

Lavaca County, Texas is in USDA Zone 8b. The average last spring frost is February 26 and the first fall frost is December 1, giving you a growing season of approximately 278 days.

At an elevation of 254 feet, Lavaca County receives approximately 60.4 inches of rainfall annually with predominantly loam soil. Summer highs average 94ยฐF, 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.

Lavaca County, TX (Zone 8b) Year-round
278 days
Last Spring Frost February 26
278 growing days
First Fall Frost December 1

Lavaca County Soil Profile

Soil Type

Loam

Soil pH

6.2-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (127 days to spare)
Start indoors: Dec 25 Transplant: Feb 26 🍅 Harvest: May 28 – Jul 16
Recommended (50%) ✓ Fits season (124 days to spare)
Start indoors: Jan 8 Transplant: Mar 12 🍅 Harvest: Jun 11 – Jul 30
Safe Start (90%) ✓ Fits season (118 days to spare)
Start indoors: Jan 31 Transplant: Apr 4 🍅 Harvest: Jul 4 – Aug 22

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 Lavaca County

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

Soil pH

Your soil pH (6.2โ€“7.8) is more alkaline than Sweet Potatoes prefers (5.5โ€“6.5). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Lavaca County is excellent for Sweet Potatoes โ€” good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Sweet Potatoes.

Organic Matter

Organic matter is moderate (2.3%). 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
0.9″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 970 gal / 100 sq ft

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€” 1.4" 0" โ„๏ธ Dormant
Feb 4.3" 1.9" 2.4" ๐Ÿšฟ Regular watering
Mar 4.3" 3.5" 0.8" ๐Ÿ’ง Light watering
Apr 4.3" 5.9" 0" โœ… Rainfall sufficient
May 4.3" 8.6" 0" โœ… Rainfall sufficient
Jun 4.3" 10.9" 0" โœ… Rainfall sufficient
Jul 4.3" 7.4" 0" โœ… Rainfall sufficient
Aug 4.3" 7.7" 0" โœ… Rainfall sufficient
Sep 4.3" 5.1" 0" โœ… Rainfall sufficient
Oct 4.3" 3.7" 0.6" ๐Ÿ’ง Light watering
Nov 4.3" 2.4" 1.9" ๐Ÿ’ง Light watering
Dec 4.3" 1.9" 2.4" ๐Ÿšฟ Regular watering

Water needs are for active growing months only (Febโ€“Dec in Lavaca 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 ~2,152 GDD — county provides 5,719 GDD Excellent fit

Sweet Potatoes Planting Timeline โ€” Lavaca County, TX

Sweet Potatoes Planting Calendar

Activity When Date Range
Start Indoors January 8 Jan 8 โ€“ Jan 22
Transplant Outdoors March 12 Mar 12 โ€“ Mar 26
Direct Sow March 5 Mar 5 โ€“ Mar 26
Harvest June 11 Jun 11 โ€“ Jul 30

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 โ€”
May โ€”
June Harvest
July Harvest
August โ€”
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 1-2 times/week

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

278 days in Lavaca County

Growing Tips for Sweet Potatoes in Lavaca County

Direct sow Sweet Potatoes outdoors after February 26 in Lavaca 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

  • Squash Summer

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

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

Lavaca County is in Zone 8b with an average last frost of February 26. Plan your Sweet Potatoes planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Lavaca County, TX?

Lavaca County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is February 26 and first fall frost is December 1.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Lavaca 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 Lavaca County, TX. Local conditions may vary. Last updated: April 2026.