Union County Soil Data
Union County, New Mexico
USDA SSURGO / PHZMAvg pH
7.3
Texture
Loam
Drainage
N/A
Organic Matter
1.6%
Hydrologic Group
D
Data Story
About Soil in Union County, New Mexico
Alkaline Grassland Foundations
Union County soils feature an average pH of 7.32, which is more acidic than the state average of 7.48. This level remains significantly higher than the national median of 6.5, reflecting its semi-arid environment.
Balanced Texture Ratios
The soil contains a balanced mix of 43.6% sand, 32.3% silt, and 21.2% clay. This composition provides a stable structure that offers better drainage and workability than many other desert regions.
Above-Average Growing Potential
With 1.57% organic matter, these soils beat the state average of 1.27%. The available water capacity of 0.138 in/in also exceeds the state benchmark, indicating a higher natural potential for plant growth.
Stable and Productive Land
The county boasts a soil score of 30.0, which is much higher than the state average of 22.2. This high score suggests the land has superior physical properties for both agriculture and structural stability.
Productive Gardening in Zone 6b
Sitting in Hardiness Zone 6b, Union County is excellent for growing hardy vegetables and prairie grasses. Utilize the relatively high fertility to start a productive kitchen garden or a small orchard.
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
Soil Amendment Products
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Browse Soil AmendmentsFrequently Asked Questions
What type of soil does Union County have?
Union County's soil is classified as Loam. This indicates the relative proportions of sand, silt, and clay — 44% sand, 32% silt, and 21% clay. Loamy soils hold moisture well and support a wide range of plants.
Is Union County's soil acidic or alkaline?
Union County's soil has a pH of 7.3, which is near neutral. This range is ideal for most garden plants and field crops.
What is the drainage class for Union County?
Drainage class data is not currently available for Union County.
What crops or plants grow well in Union County's soil?
Based on Union County's Loam texture, pH of 7.3, and drainage class, the soil is well suited for drought-tolerant crops and native grasses, row crops and vegetable gardens.
What USDA soil order is found in Union County?
The dominant USDA soil order for Union County is not currently available in our dataset.
Soil & Planting Advisory: Union County
Soil Verdict
Union County is in USDA hardiness zone 6b, a moderate climate zone. where winter lows can reach -5°F. Freeze-thaw cycles are moderate; soil biology slows in winter but recovers reliably in spring, supporting a broad range of plants.
Planting Guidance
A wide plant palette is possible: deciduous trees, most shrubs, cool-season vegetables, and many perennials thrive here. 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
Moderate freeze-thaw cycles naturally aerate the soil but can also cause compaction in clay-heavy areas; annual core aeration is beneficial. Organic matter amendments decompose at a moderate pace — aim for 3-5% organic content for optimal fertility. When soil temperatures drop below freezing, microbial nitrogen cycling stops; spring fertilization is more effective than late-fall application.
Regional Context
Union County is somewhat cooler than the New Mexico statewide average.
Planning your lawn? View lawn care data for Union County on LawnByCounty.com →
Other Counties in New Mexico
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.