Loudoun County Soil Data
Loudoun County, Virginia
USDA SSURGO / PHZMAvg pH
5.1
Texture
Loam
Drainage
N/A
Organic Matter
1.5%
Hydrologic Group
N/A
Data Story
About Soil in Loudoun County, Virginia
Deeply Acidic Piedmont Soils
Loudoun’s soils are quite acidic with an average pH of 5.07, falling well below the Virginia state average of 5.23. This level of acidity can lock away essential nutrients, often requiring regular lime applications for most turf and garden crops.
Silty Texture and Low Sand
A silt-heavy mix of 49.9% gives the soil a smooth texture, while the low sand content of 29.0% can make it feel heavy when wet. This composition provides a stable base for construction but may require aeration for optimal plant root growth.
Low Natural Organic Matter
Organic matter sits at a low 1.52%, trailing both the national average of 2.0% and the state average of 2.90%. Gardeners should prioritize adding compost and leaf mold to improve the soil's biological health.
Resilient Water Capacity
Despite low organic matter, the soil maintains a water capacity of 0.159 in/in, which is better than the state average of 0.143. This high capacity helps offset some of the drainage issues associated with silty textures.
Smart Gardening in Zone 7a
Gardeners in zone 7a should focus on acid-loving plants like blueberries and azaleas which thrive in these conditions. With a soil score of 23.3, success often depends on active soil management and amendment.
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 5.1. These products help balance soil pH for healthier grass.
Browse Soil AmendmentsFrequently Asked Questions
What type of soil does Loudoun County have?
Loudoun County's soil is classified as Loam. This indicates the relative proportions of sand, silt, and clay — 29% sand, 50% silt, and 18% clay. Loamy soils hold moisture well and support a wide range of plants.
Is Loudoun County's soil acidic or alkaline?
Loudoun County's soil has a low pH of 5.1, which is strongly acidic. Acidic soils benefit from lime applications to raise pH and improve nutrient availability.
What is the drainage class for Loudoun County?
Drainage class data is not currently available for Loudoun County.
What crops or plants grow well in Loudoun County's soil?
Based on Loudoun County's Loam texture, pH of 5.1, and drainage class, the soil is well suited for acid-loving plants like blueberries and azaleas, row crops and vegetable gardens.
What USDA soil order is found in Loudoun County?
The dominant USDA soil order for Loudoun County is not currently available in our dataset.
Soil & Planting Advisory: Loudoun County
Soil Verdict
Loudoun 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
Loudoun County closely matches the Virginia 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 Loudoun County on LawnByCounty.com →
Other Counties in Virginia
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.