Clark County Soil Data
Clark County, South Dakota
USDA SSURGO / PHZMAvg pH
7.1
Texture
Loam
Drainage
N/A
Organic Matter
4.0%
Hydrologic Group
N/A
Data Story
About Soil in Clark County, South Dakota
High-performing alkaline soils in Clark
With a soil score of 65.7, Clark County outpaces the state average for overall quality. The 7.14 average pH is slightly alkaline compared to the national 6.5 median but supports vigorous plant growth.
Fine textures for field crops
The soil mix contains 42.4% silt and 33.8% sand, which creates a versatile texture for large-scale farming. A clay content of 23.8% provides the necessary structure to prevent nutrient leaching.
Rich organic matter leads the state
Clark County boasts a high organic matter content of 4.04%, significantly higher than the state average of 3.75%. This richness is paired with a superior available water capacity of 0.193 in/in.
Superior moisture management
Specific drainage classifications are not provided, but the high soil score suggests excellent hydrology for agriculture. The high organic content helps the soil act as a sponge, holding water for dry periods.
Maximum yields in zone 4b
Despite the cold Zone 4b winters, these soils are among the best in the state for productivity. You can grow high-yield vegetable gardens or standard row crops with confidence in this high-OM soil.
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
Drainage class data not available.
Soil Profile
Dominant texture: 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 Loam. This indicates the relative proportions of sand, silt, and clay — 34% sand, 42% silt, and 24% 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 7.1, which is near neutral. This range is ideal for most garden plants and field crops.
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 7.1, and drainage class, the soil is well suited for drought-tolerant crops and native grasses, 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 4b, a cold climate zone. where winter lows can reach -25°F. Soils here experience deep freeze cycles that can disrupt structure, kill shallow roots, and slow microbial activity for months each year.
Planting Guidance
Focus on cold-hardy perennials, native grasses, and conifers. The short growing window favors plants with low heat requirements. With extreme winter lows, any marginally hardy plants need heavy mulch and wind protection. 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
Deep winter freezing can create soil heaving that pushes shallow-rooted plants out of the ground; add 3-4 inches of organic mulch each fall. Soil drainage is critical — frozen, waterlogged soil kills roots faster than cold alone. 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 South Dakota average hardiness conditions.
Planning your lawn? View lawn care data for Clark County on LawnByCounty.com →
Other Counties in South Dakota
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.