Clark County Soil Data
Clark County, Arkansas
USDA SSURGO / PHZMAvg pH
5.6
Texture
Loam
Drainage
N/A
Organic Matter
1.6%
Hydrologic Group
D
Data Story
About Soil in Clark County, Arkansas
Matching the State's Acidic Average
With a pH of 5.57, Clark County soil matches the Arkansas average almost perfectly. This level is significantly more acidic than the national median of 6.5, often requiring lime to balance the soil for traditional vegetable gardens. While the specific taxonomic order remains unspecified, the chemical profile is typical for the southern Arkansas timberlands.
A Workable Sandy Mix
A balanced mix of 46.1% sand and 36.0% silt provides a workable structure that allows for decent aeration. The remaining 17.9% clay helps hold onto essential minerals without making the ground too heavy. This composition is generally easy to till and offers a good environment for root development.
Modest Organic Matter Levels
The organic matter level of 1.62% is lower than the 4.15% state average and the 2.0% national benchmark. The available water capacity is 0.141 in/in, which sits slightly below the state average of 0.148 in/in. Gardeners should consider adding compost to improve nutrient retention and moisture levels.
High Runoff Potential in Group D
The land falls into Hydrologic Group D, which indicates very low infiltration rates when the ground is thoroughly wet. This suggests a high potential for surface runoff, meaning water moves across the surface rather than soaking in quickly. You should plan for drainage solutions around foundations and in low-lying garden beds.
Southern Favorites in Zone 8a
The mild winters of Zone 8a allow for a wide variety of southern-friendly crops and perennials. Azaleas and heat-tolerant tomatoes thrive here when the soil is properly amended. Despite a modest soil score of 30.0, the workable texture makes it a rewarding place to start a backyard plot.
Soil Composition
Soil pH
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.
Drainage Class
Drainage class data not available.
Soil Profile
Dominant texture: Loam
Typical soil profile. Actual depths vary by location.
USDA Soil Orders
Acidic Soil Detected
Your county's average pH is 5.6. These products help balance soil pH for healthier grass.
Browse Soil AmendmentsFrequently Asked Questions
What type of soil does Clark County have?
Clark County's soil is classified as Loam. This indicates the relative proportions of sand, silt, and clay — 46% sand, 36% silt, and 18% clay. Loamy soils hold moisture well and support a wide range of plants.
Is Clark County's soil acidic or alkaline?
Clark County's soil has a pH of 5.6, which is moderately acidic. This range suits many crops and is common across much of the eastern US.
What is the drainage class for Clark County?
Drainage class data is not currently available for Clark County.
What crops or plants grow well in Clark County's soil?
Based on Clark County's Loam texture, pH of 5.6, and drainage class, the soil is well suited for vegetables, grains, and most field crops, row crops and vegetable gardens.
What USDA soil order is found in Clark County?
The dominant USDA soil order for Clark County is not currently available in our dataset.
Soil & Planting Advisory: Clark County
Soil Verdict
Clark County is in USDA hardiness zone 8a, a warm climate zone. where winter lows can reach 10°F. Mild winters mean soil rarely freezes deeply, allowing year-round microbial activity and faster organic matter breakdown.
Planting Guidance
Warm-season crops, citrus relatives, and heat-loving ornamentals do well. Cool-season vegetables should be planted in fall and winter. Always match plant selections to the specific microclimate of your property — low spots, slopes, and wind exposure can shift effective hardiness by half a zone.
Soil Implications
Warm soils accelerate organic matter breakdown, so compost and mulch need replenishing more frequently than in cooler zones. Sandy soils common in warm zones drain quickly; water-retentive amendments like compost or peat help hold moisture.
Regional Context
Clark County closely matches the Arkansas average hardiness conditions.
Planning your lawn? View lawn care data for Clark County on LawnByCounty.com →
Other Counties in Arkansas
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.