Poweshiek County Soil Data
Poweshiek County, Iowa
USDA SSURGO / PHZMAvg pH
6.3
Texture
Silt Loam
Drainage
N/A
Organic Matter
2.8%
Hydrologic Group
N/A
Data Story
About Soil in Poweshiek County, Iowa
Slightly Acidic Central Iowa Earth
Poweshiek County soils have an average pH of 6.30, slightly more acidic than the state average of 6.43. The overall soil score of 66.5 reflects a landscape with distinct management needs.
High Silt and Moderate Clay
Silt dominates the profile at 56.8%, paired with 24.9% clay. This creates a dense soil structure that excels at holding nutrients but can be prone to surface crusting after heavy rains.
Building Organic Matter for Success
The organic matter level is 2.77%, which is lower than the Iowa average of 3.81%. With an available water capacity of 0.186 in/in, careful moisture management is necessary for peak production.
Moisture Management in Silt
The soil's high silt content means it holds water longer than sandy soils. Without specific drainage data, land managers should focus on maintaining soil structure to ensure healthy water infiltration.
Garden Potential in Zone 5b
This Zone 5b region is fantastic for growing potatoes, carrots, and onions. Start your garden today and use mulch to help improve the soil's natural organic levels over time.
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
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Browse Soil AmendmentsFrequently Asked Questions
What type of soil does Poweshiek County have?
Poweshiek County's soil is classified as Silt Loam. This indicates the relative proportions of sand, silt, and clay — 18% sand, 57% silt, and 25% clay. Loamy soils hold moisture well and support a wide range of plants.
Is Poweshiek County's soil acidic or alkaline?
Poweshiek 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 Poweshiek County?
Drainage class data is not currently available for Poweshiek County.
What crops or plants grow well in Poweshiek County's soil?
Based on Poweshiek 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 Poweshiek County?
The dominant USDA soil order for Poweshiek County is not currently available in our dataset.
Soil & Planting Advisory: Poweshiek County
Soil Verdict
Poweshiek County is in USDA hardiness zone 5b, a cold climate zone. where winter lows can reach -15°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
Poweshiek County closely matches the Iowa average hardiness conditions. The zone range of 5a-5b within the county means soil and planting decisions should account for local elevation and topography.
Planning your lawn? View lawn care data for Poweshiek 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.