Caldwell County Soil Data

Caldwell County, Texas

Avg pH

7.3

Texture

Gravelly loam

Drainage

Moderately well drained

Organic Matter

1.7%

Hydrologic Group

D

Data Story

About Soil in Caldwell County, Texas

Gravelly Loams of the Alfisol Order

Caldwell County is dominated by Alfisols with a gravelly loam texture that provides a sturdy base for development and farming. The average pH of 7.30 is slightly more alkaline than the national median of 6.5 and the state average of 7.09. This alkaline lean may require specific plant choices that tolerate higher lime content.

A Gritty and Clay-Rich Blend

The soil features a composition of 42.8% sand and 29.2% clay, creating a heavy but workable profile. This higher clay percentage helps the soil stay firm, but it can become quite sticky when saturated. The 28.0% silt content adds a smooth texture that aids in nutrient delivery to plant roots.

Superior Water Retention and Health

Organic matter stands at 1.69%, slightly outperforming the Texas state average of 1.66%. With an available water capacity of 0.136 in/in, these soils hold more moisture than the typical Texas plot. This storage capacity is a major asset for surviving the intense summer heat waves.

Moderately Drained but Heavy Soils

The county is moderately well drained, but it belongs to hydrologic group D, indicating high runoff potential. Because water moves slowly through the deeper clay layers, managing surface drainage is essential for preventing ponding. This setup is excellent for farm ponds but requires care when planning garden beds.

Gardening Success in Zone 9a

As a Zone 9a region, Caldwell County enjoys mild winters and a long, productive growing season. Fig trees, tomatoes, and zinnias find the alkaline, water-retentive soil very much to their liking. Pick up a shovel and start your garden today to enjoy the bounty of this rich Texas earth.

Soil Composition

Gravelly loam
Sand: 42.8%
Silt: 28.0%
Clay: 29.2%
Gravelly loam

Soil pH

7.3pH
7.3039820153921
Strongly AcidicSlightly AcidicNeutralSlightly AlkalineStrongly Alkaline
Ideal lawn range: 6.0 - 7.0

Soil Series

Detailed soil series data not yet available for this county.

Hydrologic Group

Group D — High Runoff

Clay soils with very slow infiltration rates. Highest runoff potential. These soils have a permanent high water table or are shallow over impervious material.

Runoff potential:High

Drainage Class

Moderately well drained

Water is removed somewhat slowly. May have a slowly permeable layer or seasonal water table.

Soil Profile

Dominant texture: Gravelly loam

O HorizonOrganic layer
0-2"
A HorizonTopsoil
2-10"
B HorizonSubsoil
10-30"
C HorizonParent material
30-60"
R HorizonBedrock
60"+

Typical soil profile. Actual depths vary by location.

Frequently Asked Questions

What type of soil does Caldwell County have?

Caldwell County's soil is classified as Gravelly loam. This indicates the relative proportions of sand, silt, and clay — 43% sand, 28% silt, and 29% clay. Loamy soils hold moisture well and support a wide range of plants.

Is Caldwell County's soil acidic or alkaline?

Caldwell County's soil has a pH of 7.3, which is near neutral. This range is ideal for most garden plants and field crops.

What is the drainage class for Caldwell County?

Caldwell County has a dominant drainage class of "Moderately well drained." Well-drained soils allow excess water to move through quickly, reducing waterlogging risk and supporting most field and garden crops.

What crops or plants grow well in Caldwell County's soil?

Based on Caldwell County's Gravelly loam texture, pH of 7.3, and Moderately well drained, the soil is well suited for drought-tolerant crops and native grasses, row crops and vegetable gardens, most annual and perennial crops.

What USDA soil order is found in Caldwell County?

Caldwell County's dominant soil order is Alfisols. Alfisols are moderate to high base-status soils with a clay-enriched subsoil. They support productive forests and cropland across temperate regions.

Other Counties in Texas

Soil data sourced from USDA SSURGO via Soil Data Access. Data is informational only and should not be used as a substitute for on-site soil testing. Contact your local NRCS office for site-specific soil information.