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When to Plant Sweet Potatoes in Kendall 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.

Kendall County, Texas is in USDA Zone 8a. The average last spring frost is March 9 and the first fall frost is November 20, giving you a growing season of approximately 256 days.

At an elevation of 2,187 feet, Kendall County receives approximately 54.6 inches of rainfall annually with predominantly loam soil. Summer highs average 95ยฐF, so Sweet Potatoes may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sweet Potatoes root diseases.

Kendall County, TX (Zone 8a) Long season
256 days
Last Spring Frost March 9
256 growing days
First Fall Frost November 20

Kendall County Soil Profile

Soil Type

Loam

Soil pH

6.4-7.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (103 days to spare)
Start indoors: Jan 10 Transplant: Mar 14 🍅 Harvest: Jun 13 – Aug 1
Recommended (50%) ✓ Fits season (102 days to spare)
Start indoors: Jan 19 Transplant: Mar 23 🍅 Harvest: Jun 22 – Aug 10
Safe Start (90%) ✓ Fits season (94 days to spare)
Start indoors: Feb 17 Transplant: Apr 21 🍅 Harvest: Jul 21 – Sep 8

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 Kendall County

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

Soil pH

Your soil pH (6.4โ€“7.4) 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 Kendall County is excellent for Sweet Potatoes โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.1%). 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
0.1″/week
Watering frequency Only during dry spells
Season total 237 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€” 1.5" 0" โ„๏ธ Dormant
Feb โ€” 2.2" 0" โ„๏ธ Dormant
Mar 4.3" 3.3" 1" ๐Ÿ’ง Light watering
Apr 4.3" 6.5" 0" โœ… Rainfall sufficient
May 4.3" 7.6" 0" โœ… Rainfall sufficient
Jun 4.3" 8.2" 0" โœ… Rainfall sufficient
Jul 4.3" 6.9" 0" โœ… Rainfall sufficient
Aug 4.3" 6.3" 0" โœ… Rainfall sufficient
Sep 4.3" 5.4" 0" โœ… Rainfall sufficient
Oct 4.3" 3.4" 0.9" ๐Ÿ’ง Light watering
Nov 4.3" 1.9" 2.4" ๐Ÿšฟ Regular watering
Dec โ€” 1.3" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Kendall 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 ~2,231 GDD — county provides 5,440 GDD Excellent fit

Sweet Potatoes Planting Timeline โ€” Kendall County, TX

Sweet Potatoes Planting Calendar

Activity When Date Range
Start Indoors January 19 Jan 19 โ€“ Feb 2
Transplant Outdoors March 23 Mar 23 โ€“ Apr 6
Direct Sow March 16 Mar 16 โ€“ Apr 6
Harvest June 22 Jun 22 โ€“ Aug 10

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

Month-by-Month Timeline

MonthActivities
January Start Indoors
February Start Indoors
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 Only during dry spells

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 8a

๐Ÿ“† Growing Season

256 days in Kendall County

Growing Tips for Sweet Potatoes in Kendall County

Direct sow Sweet Potatoes outdoors after March 09 in Kendall 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 Kendall County, TX?

Kendall County is in Zone 8a with an average last frost of March 9. Plan your Sweet Potatoes planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Kendall County, TX?

Kendall County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 9 and first fall frost is November 20.

๐ŸŒฑ

Plan Your Garden with Confidence

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

Get Your Free Garden Planner →

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