Grant County Soil Data

Grant County, Washington

Avg pH

7.3

Texture

Silt loam

Drainage

Well drained

Organic Matter

1.4%

Hydrologic Group

B

Data Story

About Soil in Grant County, Washington

Classic Aridisols of the Desert

Grant County is dominated by Aridisols with an average pH of 7.28, which is more alkaline than the national median of 6.5. This high pH is typical of arid climates where minerals accumulate rather than leaching away.

Productive Silt Loam Mix

The dominant texture is silt loam, consisting of 50.2% sand and 39.7% silt. This mix, containing only 8.0% clay, offers an excellent balance of root aeration and physical stability for large-scale farming.

Irrigation Drives This Land

Organic matter is measured at 1.40%, falling below the national average of 2.0% and the state average of 14.85%. An available water capacity of 0.151 in/in makes irrigation indispensable for maintaining the county's high agricultural output.

Well-Drained for Building and Farming

The soil is classified as well-drained and belongs to Hydrologic Group B. These properties indicate a moderate infiltration rate, making the land highly suitable for both residential foundations and diverse crop types.

A Potato Growing Powerhouse

Located in Hardiness Zone 7a, Grant County is one of the nation's top producers of potatoes and tree fruits. The well-drained silt loam is ready for your home garden—start planting today and watch it thrive.

Soil Composition

Silt loam
Sand: 50.2%
Silt: 39.7%
Clay: 8.0%
Silt loam

Soil pH

7.3pH
7.27707822627611
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 B — Moderate Runoff

Moderately deep, moderately well-drained soils with moderate infiltration rates. Good balance of drainage and water retention.

Runoff potential:Moderate

Drainage Class

Well drained

Water is removed from the soil readily but not rapidly. Optimal for most plants and construction.

Soil Profile

Dominant texture: Silt 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 Grant County have?

Grant County's soil is classified as Silt loam. This indicates the relative proportions of sand, silt, and clay — 50% sand, 40% silt, and 8% clay. Loamy soils hold moisture well and support a wide range of plants.

Is Grant County's soil acidic or alkaline?

Grant 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 Grant County?

Grant County has a dominant drainage class of "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 Grant County's soil?

Based on Grant County's Silt loam texture, pH of 7.3, and 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 Grant County?

Grant County's dominant soil order is Aridisols. Aridisols are soils of dry environments with low organic matter. They often have salt or calcium carbonate accumulations at depth.

Other Counties in Washington

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.