County soil summary
Soil types in Hidalgo County, Texas
The most widespread soils are Hidalgo, Brennan and Nueces; the most common drainage class is well drained (62% of the land), and typical topsoil pH is 7.2.
- Well or moderately well drained
- 90% of land · state 88%
- Typical topsoil pH
- 7.2 neutral · state 7.5
- Septic fields very limited
- 27% of land · state 71%
- Subject to flooding
- 4% of land, any frequency · state 10%
Most common soils in Hidalgo County
Share of mapped land
A county is a patchwork of many soils. These 8 cover 63% of the mapped land; 43 named soil series are mapped here in all.
| Soil | Share of land | Drainage | Topsoil pH |
|---|---|---|---|
| Hidalgo | 19.1% | Well drained | 8.2 |
| Brennan | 9.3% | Well drained | 7.2 |
| Nueces | 9.1% | Moderately well drained | 6.5 |
| Mcallen | 6.2% | Well drained | 8.2 |
| UnnamedGeneral soil group, not a named series | 5.0% | — | — |
| Willacy | 4.9% | Well drained | 7.2 |
| Harlingen | 4.6% | Moderately well drained | 8.2 |
| Raymondville | 4.4% | Moderately well drained | 8.2 |
What this means
What the soils in Hidalgo County mean for gardens, lawns and septic systems
For your garden
Typical topsoil in Hidalgo County is neutral: pH 7.2 (most land between 6.5 and 8.2), the range most vegetables, flowers and lawn grasses prefer.
Loamy topsoil (loam, silt loam and similar) covers 57% of the land: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is fine sandy loam (33% of the land).
90% of the land is moderately well to excessively drained, which suits most garden plants.
For your lawn and yard
Most land is in hydrologic groups B and C, where rain soaks in at a moderate pace.
For a septic system
For conventional septic absorption fields, NRCS rates 27% of the land in Hidalgo County very limited, 54% somewhat limited and 4% not limited (16% not rated, such as urban land, pits or water).
Statewide, 71% of the land is very limited, so Hidalgo County is less restrictive than typical.
Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.
Drainage
How long the soil stays wet
The most common drainage class is well drained (62%). 90% of the land is moderately well drained or better, compared with 88% across Texas.
Show as a table
| Category | Hidalgo County | Texas |
|---|---|---|
| Excessively drained | 0.0% | 1.0% |
| Somewhat excessively drained | 0.9% | 1.4% |
| Well drained | 61.8% | 69.9% |
| Moderately well drained | 27.5% | 15.8% |
| Somewhat poorly drained | 1.9% | 3.7% |
| Poorly drained | 0.2% | 2.2% |
| Very poorly drained | 0.0% | 0.5% |
| Not rated | 7.9% | 5.6% |
Septic absorption fields
NRCS rating for conventional drain fields
The rating looks at the soil from 24 to 60 inches deep: permeability, depth to a seasonal water table or bedrock, flooding and slope. “Very limited” means at least one feature is unfavorable enough that a conventional field is hard to make work.
Show as a table
| Category | Hidalgo County | Texas |
|---|---|---|
| Not limited | 3.6% | 1.4% |
| Somewhat limited | 54.0% | 16.7% |
| Very limited | 26.8% | 70.9% |
| Not rated | 15.6% | 11.0% |
Rain, runoff and water table
Hydrologic soil group, flooding, seasonal water table
Hydrologic soil group
How fast rain soaks in when the soil is already wet. Group A soaks in fastest, D slowest.
Show as a table
| Category | Hidalgo County | Texas |
|---|---|---|
| A: fast infiltration (mostly sandy or gravelly) | 8.3% | 7.2% |
| B: moderate infiltration | 51.5% | 20.0% |
| C: slow infiltration | 14.0% | 22.9% |
| D: very slow infiltration (clayey, shallow or wet) | 10.6% | 38.3% |
| A/D: D as is, A if drained | 0.0% | 0.1% |
| B/D: D as is, B if drained | 0.0% | 0.8% |
| C/D: D as is, C if drained | 1.0% | 1.8% |
| Not rated | 14.6% | 8.8% |
Flooding
Show as a table
| Category | Hidalgo County | Texas |
|---|---|---|
| No flooding | 90.6% | 86.1% |
| Rare or very rare | 0.8% | 2.1% |
| Occasional | 2.6% | 3.4% |
| Frequent or very frequent | 0.2% | 4.6% |
| Not reported | 5.7% | 3.7% |
Seasonal high water table
Show as a table
| Category | Hidalgo County | Texas |
|---|---|---|
| Within 18 inches at some time of year | 1.5% | 5.7% |
| 18 inches to 3.3 feet | 0.2% | 3.6% |
| Deeper than 3.3 feet or none reported | 94.3% | 89.0% |
| Not reported | 4.0% | 1.6% |
Topsoil pH and texture
First mineral layer of each soil
Typical topsoil pH is 7.2 (neutral); 80% of rated land falls between 6.5 and 8.2. Median topsoil organic matter is 0.8%.
Show as a table
| Category | Hidalgo County | Texas |
|---|---|---|
| Strongly acidic (below 5.5) | 0.0% | 5.2% |
| Moderately to slightly acidic (5.5–6.4) | 4.0% | 9.8% |
| Near neutral (6.5–7.3) | 38.2% | 24.9% |
| Alkaline (7.4 and up) | 41.8% | 46.8% |
| Not reported | 16.0% | 13.3% |
Texture
Show as a table
| Category | Hidalgo County | Texas |
|---|---|---|
| Sandy | 17.7% | 14.6% |
| Loamy (loam, silt loam and similar) | 57.2% | 56.0% |
| Clayey (40%+ clay) | 8.8% | 15.9% |
| Organic (muck or peat) | 0.0% | 0.1% |
| Not reported (rock, urban land, etc.) | 16.3% | 13.4% |
Sources & data dates
- Source
- USDA NRCS Soil Survey Geographic Database (SSURGO), queried through Soil Data Access. Public domain.
- Data date
- SSURGO as published on November 3, 2026 (most recent survey area update October 26, 2026). NRCS refreshes SSURGO each October.
- Scope
- Hidalgo County, Texas (FIPS 48215): 1,001,733 acres of mapped land, 10,497 acres of open water excluded. State comparisons pool all mapped land in Texas.
- Method
- Shares are by mapped land area: each map unit’s acres in the county times each soil component’s percentage. Open water is excluded. Topsoil values use the first mineral horizon of each component. Full methodology.