St. Johns County Soil Data
St. Johns County, Florida
Avg pH
5.1
Texture
Loamy Sand
Drainage
N/A
Organic Matter
10.2%
Hydrologic Group
N/A
Data Story
About Soil in St. Johns County, Florida
Acidic soils typical of the Atlantic coast
St. Johns County maintains an average soil pH of 5.09, which is less acidic than the state average of 4.88. However, this still sits well below the national median pH of 6.5. This acidic environment requires specific plant choices or regular lime applications for traditional gardening.
Balanced sand and silt mix
The soil consists of 78.6% sand, 4.0% silt, and 3.3% clay. This provides slightly more body and workability than many of its sandier Florida neighbors. The higher silt and clay percentages help slightly with nutrient retention compared to purely sandy regions.
Rich organic content for better growth
Organic matter reaches 10.19%, which is substantially higher than the national 2.0% benchmark. This high organic load results in an available water capacity of 0.123 in/in, surpassing the state average of 0.108. These metrics drive a solid soil score of 36.4.
Reliable water storage for coastal farming
Specific drainage and hydrologic group data is not available, but the soil score of 36.4 suggests high overall quality. The water capacity of 0.123 in/in helps plants survive through dry spells better than thinner soils. This makes the land generally resilient for both agriculture and development.
Cultivating the 9b coastal climate
As a zone 9b region, St. Johns is ideal for salt-tolerant ornamentals and winter vegetables. The rich 10.19% organic matter gives your plants a head start in nutrient uptake. Grab some seeds and take advantage of these fertile, coastal conditions.
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: Loamy Sand
Typical soil profile. Actual depths vary by location.
USDA Soil Orders
Frequently Asked Questions
What type of soil does St. Johns County have?
St. Johns County's soil is classified as Loamy Sand. This indicates the relative proportions of sand, silt, and clay — 79% sand, 4% silt, and 3% clay. Loamy soils hold moisture well and support a wide range of plants.
Is St. Johns County's soil acidic or alkaline?
St. Johns 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 St. Johns County?
Drainage class data is not currently available for St. Johns County.
What crops or plants grow well in St. Johns County's soil?
Based on St. Johns County's Loamy Sand 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 St. Johns County?
The dominant USDA soil order for St. Johns County is not currently available in our dataset.
Planning your lawn? View lawn care data for St. Johns County on LawnByCounty.com →
Other Counties in Florida
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.