Mahaska County Soil Data
Mahaska County, Iowa
Avg pH
6.3
Texture
Silt Loam
Drainage
N/A
Organic Matter
2.8%
Hydrologic Group
N/A
Data Story
About Soil in Mahaska County, Iowa
Standard Midwestern Agricultural Acidity
Mahaska County’s soil has a pH of 6.31, placing it just below the national median of 6.5. While taxonomic records are limited, this slightly acidic profile is typical for the region's productive agricultural land.
Dense Matrix for Root Stability
The composition is dominated by 55.3% silt and 23.9% clay, providing a dense matrix for plant roots to grip. With 20.9% sand, the soil maintains enough structure to prevent total saturation while remaining nutrient-dense.
Healthy Organic Benchmarks
Organic matter averages 2.78%, exceeding the national average of 2.0% but falling short of the state’s 3.81% benchmark. The available water capacity of 0.186 inches per inch is slightly below the state average, requiring attentive irrigation during dry spells.
Naturally Moisture-Retentive Earth
Though official drainage classes are not provided, the high silt and clay levels suggest the soil is naturally moisture-retentive. Gardeners and farmers should watch for slow drainage in low-lying areas after heavy Iowa rains.
Versatile Growing in Zone 5b
Located in hardiness zone 5b, Mahaska County is well-suited for growing corn, soybeans, and hardy garden perennials. Grab a shovel and start planting, as this soil offers a solid foundation for any green thumb.
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: Silt Loam
Typical soil profile. Actual depths vary by location.
USDA Soil Orders
Frequently Asked Questions
What type of soil does Mahaska County have?
Mahaska County's soil is classified as Silt Loam. This indicates the relative proportions of sand, silt, and clay — 21% sand, 55% silt, and 24% clay. Loamy soils hold moisture well and support a wide range of plants.
Is Mahaska County's soil acidic or alkaline?
Mahaska 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 Mahaska County?
Drainage class data is not currently available for Mahaska County.
What crops or plants grow well in Mahaska County's soil?
Based on Mahaska County's Silt Loam texture, pH of 6.3, 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 Mahaska County?
The dominant USDA soil order for Mahaska County is not currently available in our dataset.
Planning your lawn? View lawn care data for Mahaska County on LawnByCounty.com →
Other Counties in Iowa
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.