Grant County Soil Data
Grant County, Oklahoma
USDA SSURGO / PHZMAvg pH
6.5
Texture
Water
Drainage
N/A
Organic Matter
1.4%
Hydrologic Group
D
Data Story
About Soil in Grant County, Oklahoma
Grant County's Neutral Soil Advantage
Grant County boasts a high soil score of 48.8, significantly beating the state average of 35.3. Its pH of 6.47 is nearly perfect, sitting right at the national median of 6.5. This near-neutral acidity creates an ideal chemical environment for most common agricultural crops.
Silt-Heavy Soils for Nutrient Retention
At 42.3% silt, 34.6% sand, and 17.7% clay, these soils offer a high-quality texture for farming. The substantial silt content provides a smooth consistency that holds nutrients better than sandier counties. This mix represents a balanced medium that supports root development and plant stability.
Top-Tier Water Storage for Agriculture
The available water capacity of 0.154 in/in is among the best in the region, providing a safety net for crops during heatwaves. Although organic matter is lower at 1.44%, the soil's physical structure helps maximize what is available. The high overall soil score reflects this impressive water-holding potential.
Handling the Infiltration Challenge
Despite its high quality, Grant County soil falls into Hydrologic Group D, indicating slow natural drainage. This means that while the soil holds water well for plants, it does not absorb excess rainfall quickly. Managing surface water is crucial to maintaining the health of these high-value soils.
Ideal Conditions in Zone 7a
Wheat and winter grains perform exceptionally well in this 7a hardiness zone and nutrient-rich silt. The near-neutral pH means gardeners will spend less on soil amendments like lime or sulfur. It is an ideal environment for starting a productive family orchard or a large-scale vegetable garden.
Soil Composition
Soil pH
Soil Series
Detailed soil series data not yet available for this county.
Hydrologic Group
Group D — High Runoff
Clay soils with very slow infiltration rates. Highest runoff potential. These soils have a permanent high water table or are shallow over impervious material.
Drainage Class
Drainage class data not available.
Soil Profile
Dominant texture: Water
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 Grant County have?
Grant County's soil is classified as Water. This indicates the relative proportions of sand, silt, and clay — 35% sand, 42% silt, and 18% clay. Sandy soils drain quickly but may need more frequent irrigation and fertilization.
Is Grant County's soil acidic or alkaline?
Grant County's soil has a pH of 6.5, which is moderately acidic. This range suits many crops and is common across much of the eastern US.
What is the drainage class for Grant County?
Drainage class data is not currently available for Grant County.
What crops or plants grow well in Grant County's soil?
Based on Grant County's Water texture, pH of 6.5, and drainage class, the soil is well suited for vegetables, grains, and most field crops.
What USDA soil order is found in Grant County?
The dominant USDA soil order for Grant County is not currently available in our dataset.
Soil & Planting Advisory: Grant County
Soil Verdict
Grant County is in USDA hardiness zone 7a, a moderate climate zone. where winter lows can reach 0°F. Mild winters mean soil rarely freezes deeply, allowing year-round microbial activity and faster organic matter breakdown.
Planting Guidance
Warm-season crops, citrus relatives, and heat-loving ornamentals do well. Cool-season vegetables should be planted in fall and winter. 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
Warm soils accelerate organic matter breakdown, so compost and mulch need replenishing more frequently than in cooler zones. Sandy soils common in warm zones drain quickly; water-retentive amendments like compost or peat help hold moisture. When soil temperatures drop below freezing, microbial nitrogen cycling stops; spring fertilization is more effective than late-fall application.
Regional Context
Grant County closely matches the Oklahoma average hardiness conditions.
Planning your lawn? View lawn care data for Grant County on LawnByCounty.com →
Other Counties in Oklahoma
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.