Harris County Soil Data
Harris County, Texas
USDA SSURGO / PHZMAvg pH
4.8
Texture
Loam
Drainage
N/A
Organic Matter
1.5%
Hydrologic Group
D
Data Story
About Soil in Harris County, Texas
Acidic Ground in the Houston Metro
Harris County soil is quite acidic, measuring a pH of 4.76 against the national 6.5 median. This acidity is a defining characteristic for local gardeners who must often adjust their soil for specific vegetables.
Sandy Silts Dominant the Profile
The soil consists of 40.0% sand, 30.7% silt, and 15.7% clay. This mix can become heavily compacted in urban environments, often requiring aeration to maintain plant health.
Fertility Near the State Average
Organic matter levels sit at 1.54%, which is slightly lower than the Texas state average of 1.66%. The available water capacity of 0.131 in/in also falls just below the state benchmark.
Hydrologic Group D Impacts Drainage
Harris County belongs to hydrologic group D, which means the soil has very slow infiltration rates. This slow movement of water contributes to the drainage challenges frequently seen across the region.
Year-Round Growing in Zone 9b
Gardeners in zone 9b can grow citrus and heat-loving herbs all year. While the 12.6 soil score is low, using raised beds helps bypass drainage issues and lets you take advantage of the long growing season.
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: Loam
Typical soil profile. Actual depths vary by location.
USDA Soil Orders
Acidic Soil Detected
Your county's average pH is 4.8. These products help balance soil pH for healthier grass.
Browse Soil AmendmentsFrequently Asked Questions
What type of soil does Harris County have?
Harris County's soil is classified as Loam. This indicates the relative proportions of sand, silt, and clay — 40% sand, 31% silt, and 16% clay. Loamy soils hold moisture well and support a wide range of plants.
Is Harris County's soil acidic or alkaline?
Harris County's soil has a low pH of 4.8, which is strongly acidic. Acidic soils benefit from lime applications to raise pH and improve nutrient availability.
What is the drainage class for Harris County?
Drainage class data is not currently available for Harris County.
What crops or plants grow well in Harris County's soil?
Based on Harris County's Loam texture, pH of 4.8, 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 Harris County?
The dominant USDA soil order for Harris County is not currently available in our dataset.
Soil & Planting Advisory: Harris County
Soil Verdict
Harris County is in USDA hardiness zone 9b, a warm climate zone. where winter lows can reach 25°F. Warm winters keep soil biology active nearly year-round, accelerating decomposition but increasing pest and disease pressure in topsoil.
Planting Guidance
Tropical and subtropical plants are viable. Year-round gardening is possible, though summer heat may limit some cool-season crops. Frost is rare; tender plants can overwinter with minimal protection. 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
Rapid organic matter turnover means soils can become nutrient-poor quickly; test annually and fertilize based on results. High soil temperatures favor certain soilborne pathogens; practice crop rotation and avoid overwatering.
Regional Context
Harris County is somewhat warmer than the Texas statewide average. The zone range of 9a-9b within the county means soil and planting decisions should account for local elevation and topography.
Planning your lawn? View lawn care data for Harris County on LawnByCounty.com →
Other Counties in Texas
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.