Clark County Soil Data
Clark County, Missouri
USDA SSURGO / PHZMAvg pH
6.3
Texture
Silt Loam
Drainage
Subaqueous
Organic Matter
2.7%
Hydrologic Group
N/A
Data Story
About Soil in Clark County, Missouri
Clark County’s Balanced pH
Clark County soils maintain an average pH of 6.30, placing them slightly above the Missouri state average of 6.09. This healthy pH level supports high biological activity and nutrient availability for local crops.
Sand and Silt Mix
The soil is notable for having 27.2% sand, which is higher than many surrounding counties, combined with 53.7% silt. This blend improves drainage and aeration compared to the heavy clay soils found elsewhere in the state.
Superior Moisture Reservoir
With an available water capacity of 0.204 in/in, this soil is one of the best in the state for moisture retention. While the 2.68% organic matter is below the state average, the county still earns a strong 73.1 soil score.
Deep Roots and Soil Health
While specific drainage and taxonomic classifications are not fully detailed in recent records, the high water capacity suggests deep, fertile profiles. These soils are generally well-regarded for their agricultural resilience.
Garden Readiness in Zone 6a
The 6a hardiness zone is ideal for cool-season vegetables and hearty fruit trees. Your plants will benefit from the high moisture-holding capacity of these sandy-silt loams during the heat of August.
Soil Composition
Soil pH
Soil Series
Detailed soil series data not yet available for this county.
Hydrologic Group
Hydrologic group data not available.
Drainage Class
Subaqueous
Drainage class: Subaqueous
Soil Profile
Dominant texture: Silt Loam
Typical soil profile. Actual depths vary by location.
USDA Soil Orders
Soil Amendment Products
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Browse Soil AmendmentsFrequently Asked Questions
What type of soil does Clark County have?
Clark County's soil is classified as Silt Loam. This indicates the relative proportions of sand, silt, and clay — 27% sand, 54% silt, and 19% 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 6.3, 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?
Clark County has a dominant drainage class of "Subaqueous." Moderate drainage allows adequate moisture retention while still permitting excess water to drain over time.
What crops or plants grow well in Clark County's soil?
Based on Clark County's Silt Loam texture, pH of 6.3, and Subaqueous, 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 6a, a moderate climate zone. where winter lows can reach -10°F. Freeze-thaw cycles are moderate; soil biology slows in winter but recovers reliably in spring, supporting a broad range of plants.
Planting Guidance
A wide plant palette is possible: deciduous trees, most shrubs, cool-season vegetables, and many perennials thrive here. Winter protection (mulch, burlap wraps) helps push the zone boundary for desired species. 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
Moderate freeze-thaw cycles naturally aerate the soil but can also cause compaction in clay-heavy areas; annual core aeration is beneficial. Organic matter amendments decompose at a moderate pace — aim for 3-5% organic content for optimal fertility. When soil temperatures drop below freezing, microbial nitrogen cycling stops; spring fertilization is more effective than late-fall application.
Regional Context
Clark County closely matches the Missouri average hardiness conditions.
Planning your lawn? View lawn care data for Clark County on LawnByCounty.com →
Other Counties in Missouri
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.