Putnam County Soil Data
Putnam County, Ohio
USDA SSURGO / PHZMAvg pH
6.2
Texture
Loam
Drainage
Moderately well drained
Organic Matter
3.3%
Hydrologic Group
B/D
Data Story
About Soil in Putnam County, Ohio
Productive Alfisols of Putnam
Putnam County's soil is dominated by Alfisols with a loam texture and a pH of 6.24. This pH level is slightly higher than the state average, making it favorable for most traditional midwestern crops.
Increased Sand and Clay Content
The composition features 34.1% sand and 24.4% clay, giving it a bit more structure than neighboring counties. With 40.8% silt, the soil is well-balanced for both nutrient retention and physical stability.
Moderate Fertility Profile
The organic matter sits at 3.32%, outperforming the national average of 2.0%. However, the available water capacity of 0.173 in/in is slightly below the state average of 0.186, suggesting a need for consistent irrigation.
Variable Drainage Potential
Classified as moderately well drained, this soil belongs to hydrologic group B/D. Depending on the specific site, the ground can offer moderate to low runoff potential, which is important for managing agricultural fields.
Farming Success in Zone 6a
Putnam County provides a solid foundation with a 63.0 soil score and a 6a hardiness zone. It is a prime location for field crops and hardy vegetables that thrive in well-structured loam.
Soil Composition
Soil pH
Soil Series
Detailed soil series data not yet available for this county.
Hydrologic Group
Group B — Moderate Runoff
Moderately deep, moderately well-drained soils with moderate infiltration rates. Good balance of drainage and water retention.
Drainage Class
Moderately well drained
Water is removed somewhat slowly. May have a slowly permeable layer or seasonal water table.
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 Putnam County have?
Putnam County's soil is classified as Loam. This indicates the relative proportions of sand, silt, and clay — 34% sand, 41% silt, and 24% clay. Loamy soils hold moisture well and support a wide range of plants.
Is Putnam County's soil acidic or alkaline?
Putnam County's soil has a pH of 6.2, which is moderately acidic. This range suits many crops and is common across much of the eastern US.
What is the drainage class for Putnam County?
Putnam County has a dominant drainage class of "Moderately well drained." Well-drained soils allow excess water to move through quickly, reducing waterlogging risk and supporting most field and garden crops.
What crops or plants grow well in Putnam County's soil?
Based on Putnam County's Loam texture, pH of 6.2, and Moderately well drained, the soil is well suited for vegetables, grains, and most field crops, row crops and vegetable gardens, most annual and perennial crops.
What USDA soil order is found in Putnam County?
Putnam County's dominant soil order is Alfisols. Alfisols are moderate to high base-status soils with a clay-enriched subsoil. They support productive forests and cropland across temperate regions.
Soil & Planting Advisory: Putnam County
Soil Verdict
Putnam 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
Putnam County closely matches the Ohio average hardiness conditions.
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Other Counties in Ohio
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.