Grundy County Soil Data

Grundy County, Tennessee

Avg pH

5.2

Texture

Silt loam

Drainage

Moderately well drained

Organic Matter

2.1%

Hydrologic Group

C

Data Story

About Soil in Grundy County, Tennessee

High Altitude, High Acidity Ultisols

Grundy County sits on the plateau with acidic Ultisols and a silt loam texture. At a pH of 5.16, the soil is significantly more acidic than the state average of 5.35 and the national median of 6.5. This low pH level can limit the availability of key nutrients like phosphorus and calcium without proper amendments.

Sandy Silt Loam with Good Aeration

The soil is a mix of 44.8% silt, 36.0% sand, and 19.2% clay. This relatively high sand content compared to other Tennessee counties improves aeration and ease of tillage. While it retains a loamy character, the sand helps water move through the surface layer more freely than in clay-heavy regions.

Meeting State Standards for Water Storage

The organic matter content is 2.11%, which is below the state average of 2.44% but slightly above the national average of 2.0%. Available water capacity stands at 0.167 in/in, nearly matching the state benchmark of 0.171. This suggests a solid foundation for plant growth if acidity is properly managed.

Moderately Well Drained with Moderate Runoff

Soils here are moderately well drained and fall into hydrologic group C. This classification means water moves through the soil at a slower rate, which can lead to higher runoff during intense plateau thunderstorms. Proper site selection is vital for avoiding soggy garden spots during the rainy season.

Mountain Gardening in Zone 7a

As a Zone 7a county, Grundy has slightly cooler winters than its neighbors, making it ideal for hardy perennials and cool-season crops. Potatoes and berries do particularly well in these acidic, well-aerated plateau soils. Embrace the unique elevation and start your mountain garden this year.

Soil Composition

Silt loam
Sand: 36.0%
Silt: 44.8%
Clay: 19.2%
Silt loam

Soil pH

5.2pH
5.15668024353119
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 C — Moderate-High Runoff

Soils with slow infiltration rates, often with a layer that impedes downward water movement. Higher clay content restricts drainage.

Runoff potential:Moderate-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: 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 Grundy County have?

Grundy County's soil is classified as Silt loam. This indicates the relative proportions of sand, silt, and clay — 36% sand, 45% silt, and 19% clay. Loamy soils hold moisture well and support a wide range of plants.

Is Grundy County's soil acidic or alkaline?

Grundy County's soil has a low pH of 5.2, which is strongly acidic. Acidic soils benefit from lime applications to raise pH and improve nutrient availability.

What is the drainage class for Grundy County?

Grundy 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 Grundy County's soil?

Based on Grundy County's Silt loam texture, pH of 5.2, and Moderately well drained, the soil is well suited for acid-loving plants like blueberries and azaleas, row crops and vegetable gardens, most annual and perennial crops.

What USDA soil order is found in Grundy County?

Grundy County's dominant soil order is Ultisols. Ultisols are highly weathered, clay-rich soils common in humid regions. They are low in natural fertility and often require lime and fertilizer for agriculture.

Other Counties in Tennessee

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.