New Castle County Soil Data
New Castle County, Delaware
USDA SSURGO / PHZMAvg pH
5.7
Texture
Loam
Drainage
N/A
Organic Matter
6.2%
Hydrologic Group
N/A
Data Story
About Soil in New Castle County, Delaware
Northern Delaware’s Acidic Foundation
New Castle County soil maintains an average pH of 5.68, placing it well below the national 6.5 neutral target. This acidic profile is characteristic of the northern region and closely tracks the state average of 5.74.
Silt-Heavy Soil Structure
With 44.4% silt and 13.5% clay, this soil is the finest in the state, offering better structural stability than its sandier southern neighbors. The 34.8% sand content balances the mix, providing a versatile medium for diverse agriculture and landscaping.
Reliable Water Retention
An available water capacity of 0.188 in/in leads the state, ensuring plants have access to moisture longer than in other Delaware counties. Although the 6.15% organic matter is lower than the state average, it remains triple the national average of 2.0%.
Robust Soil Stability
While specific drainage classifications are missing from local datasets, the high silt and clay content indicates a greater ability to hold water compared to coastal sands. These characteristics suggest a stable foundation for both farming and suburban development.
Garden Success in 7b
The county’s soil score of 64.5 makes it the highest-rated in the state for productivity and health. Hardiness Zone 7b supports long growing seasons for everything from heirloom tomatoes to ornamental shrubs.
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: Loam
Typical soil profile. Actual depths vary by location.
USDA Soil Orders
Acidic Soil Detected
Your county's average pH is 5.7. These products help balance soil pH for healthier grass.
Browse Soil AmendmentsFrequently Asked Questions
What type of soil does New Castle County have?
New Castle County's soil is classified as Loam. This indicates the relative proportions of sand, silt, and clay — 35% sand, 44% silt, and 13% clay. Loamy soils hold moisture well and support a wide range of plants.
Is New Castle County's soil acidic or alkaline?
New Castle County's soil has a pH of 5.7, which is moderately acidic. This range suits many crops and is common across much of the eastern US.
What is the drainage class for New Castle County?
Drainage class data is not currently available for New Castle County.
What crops or plants grow well in New Castle County's soil?
Based on New Castle County's Loam texture, pH of 5.7, 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 New Castle County?
The dominant USDA soil order for New Castle County is not currently available in our dataset.
Soil & Planting Advisory: New Castle County
Soil Verdict
New Castle County is in USDA hardiness zone 7b, a moderate climate zone. where winter lows can reach 5°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
New Castle County closely matches the Delaware average hardiness conditions. The zone range of 7a-7b within the county means soil and planting decisions should account for local elevation and topography.
Planning your lawn? View lawn care data for New Castle County on LawnByCounty.com →
Other Counties in Delaware
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.