Onslow County Soil Data
Onslow County, North Carolina
USDA SSURGO / PHZMAvg pH
5.2
Texture
Sand
Drainage
N/A
Organic Matter
6.1%
Hydrologic Group
N/A
Data Story
About Soil in Onslow County, North Carolina
Classic Coastal Acidity Levels
Onslow's average pH of 5.17 is almost identical to the North Carolina average of 5.14. While taxonomic data remains unspecified, this level is significantly more acidic than the national median of 6.5. This acidity is typical for the pine-heavy ecosystems found along the coast.
Dominated by Coastal Sands
The soil is highly sandy at 73.7%, with 14.8% silt and 9.0% clay making up the rest. This creates a loose, easy-to-dig texture that is common in the Atlantic Coastal Plain. Such high sand content allows for excellent air circulation around plant roots.
Rich in Organic Matter
Onslow boasts an organic matter content of 6.10%, surpassing the state average of 5.12%. However, the available water capacity of 0.110 in/in is lower than the state mean of 0.134 in/in. This means the soil is fertile but loses moisture relatively quickly during the summer heat.
Managing Rapid Water Flow
Official drainage classes are currently missing from the data, but a 73.7% sand ratio generally implies rapid drainage. Gardeners should watch for quick drying, while builders generally enjoy the stability of these sandy deposits. Proper drainage planning is essential for any local development.
Coastal Blooms in Zone 8b
In Zone 8b, Onslow County is ideal for blueberries, azaleas, and other acid-loving species. The soil score of 33.3 indicates a solid foundation that outperforms the state average. Now is the perfect time to plant your coastal garden and enjoy the long growing season.
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: Sand
Typical soil profile. Actual depths vary by location.
USDA Soil Orders
Acidic Soil Detected
Your county's average pH is 5.2. These products help balance soil pH for healthier grass.
Browse Soil AmendmentsFrequently Asked Questions
What type of soil does Onslow County have?
Onslow County's soil is classified as Sand. This indicates the relative proportions of sand, silt, and clay — 74% sand, 15% silt, and 9% clay. Sandy soils drain quickly but may need more frequent irrigation and fertilization.
Is Onslow County's soil acidic or alkaline?
Onslow County's soil has a low pH of 5.2, which is strongly acidic. Acidic soils benefit from lime applications to raise pH and improve nutrient availability.
What is the drainage class for Onslow County?
Drainage class data is not currently available for Onslow County.
What crops or plants grow well in Onslow County's soil?
Based on Onslow County's Sand texture, pH of 5.2, and drainage class, the soil is well suited for acid-loving plants like blueberries and azaleas, drought-tolerant crops, root vegetables, and sandy-soil specialists.
What USDA soil order is found in Onslow County?
The dominant USDA soil order for Onslow County is not currently available in our dataset.
Soil & Planting Advisory: Onslow County
Soil Verdict
Onslow County is in USDA hardiness zone 8b, a warm climate zone. where winter lows can reach 15°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. 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.
Regional Context
Onslow County closely matches the North Carolina average hardiness conditions. The zone range of 8a-8b within the county means soil and planting decisions should account for local elevation and topography.
Planning your lawn? View lawn care data for Onslow County on LawnByCounty.com →
Other Counties in North Carolina
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.