Sioux County Soil Data
Sioux County, Iowa
USDA SSURGO / PHZMAvg pH
6.6
Texture
Silt Loam
Drainage
N/A
Organic Matter
3.5%
Hydrologic Group
N/A
Data Story
About Soil in Sioux County, Iowa
Sioux County's Sweet Soil Profile
Sioux County soil features a pH of 6.61, which is slightly more alkaline than both the national median and the Iowa average. This 'sweet' soil is excellent for nutrient availability, particularly for legumes and grasses.
A Solid Silt and Clay Mix
The composition is 51.5% silt and 26.1% clay, providing a sturdy structure for agricultural machinery. The 21.1% sand fraction ensures that the soil remains workable and doesn't turn into a solid block when dry.
Reliable Organic Matter and Moisture
Organic matter sits at a healthy 3.51%, nearing the state average of 3.81% and easily beating national figures. The water capacity of 0.201 inches per inch is slightly above the state norm, ensuring steady growth.
Balanced Hydrology for Deep Roots
While specific drainage classes are unavailable, the silt-heavy profile typically supports deep root systems. Proper field management is key to preventing erosion in these fine-textured Northwest Iowa soils.
Success in Hardiness Zone 5a
The 5a hardiness zone is perfect for cereal grains and cool-weather vegetables like kale and peas. This soil's natural alkalinity makes it a prime candidate for a thriving home vegetable patch.
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
Soil Amendment Products
Browse products to improve your soil health and lawn performance.
Browse Soil AmendmentsFrequently Asked Questions
What type of soil does Sioux County have?
Sioux County's soil is classified as Silt Loam. This indicates the relative proportions of sand, silt, and clay — 21% sand, 52% silt, and 26% clay. Loamy soils hold moisture well and support a wide range of plants.
Is Sioux County's soil acidic or alkaline?
Sioux County's soil has a pH of 6.6, which is near neutral. This range is ideal for most garden plants and field crops.
What is the drainage class for Sioux County?
Drainage class data is not currently available for Sioux County.
What crops or plants grow well in Sioux County's soil?
Based on Sioux County's Silt Loam texture, pH of 6.6, 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 Sioux County?
The dominant USDA soil order for Sioux County is not currently available in our dataset.
Soil & Planting Advisory: Sioux County
Soil Verdict
Sioux County is in USDA hardiness zone 5a, a cold climate zone. where winter lows can reach -20°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. 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
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
Sioux County closely matches the Iowa average hardiness conditions.
Planning your lawn? View lawn care data for Sioux 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.