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Assumption Parish Soil Data

Assumption Parish, Louisiana

USDA SSURGO / PHZM

Avg pH

6.5

Texture

Clay

Drainage

N/A

Organic Matter

8.6%

Hydrologic Group

N/A

Data Story

About Soil in Assumption Parish, Louisiana

Near-Perfect Soil Chemistry

Assumption Parish features a pH of 6.45, nearly identical to the national median of 6.5. This provides an exceptional chemical environment where nutrients are most available to plants. While the specific taxonomic order is unclassified, this pH indicates a highly productive soil profile.

Dense Clay and Silt Profiles

The soil composition is 60.7% clay and 35.5% silt, with almost no sand at 3.8%. This creates a dense, heavy soil that is excellent for nutrient retention but very challenging to till. It can feel like concrete when dry and like heavy dough when wet.

Exceptional Organic Wealth

This parish stands out with 8.57% organic matter, far surpassing both the state average of 6.38% and the national average of 2.0%. While the available water capacity of 0.171 in/in is slightly below the state average, the high organic content provides incredible natural fertility. This is some of the richest soil in the region.

Slow Drainage and Heavy Runoff

The extreme clay content naturally limits drainage speed and water movement. Although specific hydrologic groups aren't listed, residents should expect slow-drying soils after storms. Raised beds are often the best solution for home gardeners to prevent waterlogged roots.

Tropical Potential in Zone 9b

Situated in the warm Zone 9b, Assumption Parish supports tropical-leaning plants and long-season crops like sugar cane. The rich, organic soil is perfect for heavy-feeding plants like corn and tomatoes. Start your garden today to take advantage of this rare, high-nutrient earth.

Soil Composition

Clay
Sand: 3.8%
Silt: 35.5%
Clay: 60.7%
Clay

Soil pH

6.5pH
6.45115467802757
Strongly AcidicSlightly AcidicNeutralSlightly AlkalineStrongly Alkaline
Ideal lawn range: 6.0 - 7.0

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: Clay

O HorizonOrganic layer
0-2"
A HorizonTopsoil
2-10"
B HorizonSubsoil
10-30"
C HorizonParent material
30-60"
R HorizonBedrock
60"+

Typical soil profile. Actual depths vary by location.

Clay Soil Detected

Clay soils can struggle with drainage. These products improve soil structure and water flow.

Browse Soil Amendments

Frequently Asked Questions

What type of soil does Assumption Parish have?

Assumption Parish's soil is classified as Clay. This indicates the relative proportions of sand, silt, and clay — 4% sand, 35% silt, and 61% clay. Clay soils retain water and nutrients but can have drainage challenges.

Is Assumption Parish's soil acidic or alkaline?

Assumption Parish's soil has a pH of 6.5, which is moderately acidic. This range suits many crops and is common across much of the eastern US.

What is the drainage class for Assumption Parish?

Drainage class data is not currently available for Assumption Parish.

What crops or plants grow well in Assumption Parish's soil?

Based on Assumption Parish's Clay texture, pH of 6.5, and drainage class, the soil is well suited for vegetables, grains, and most field crops, wetland plants and crops tolerant of slow drainage.

What USDA soil order is found in Assumption Parish?

The dominant USDA soil order for Assumption Parish is not currently available in our dataset.

Soil & Planting Advisory: Assumption Parish

Soil Verdict

Assumption Parish 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

Assumption Parish closely matches the Louisiana average hardiness conditions. The zone range of 9a-9b within the county means soil and planting decisions should account for local elevation and topography.

Other Counties in Louisiana

By Evan Brooks, Data EditorUpdated Reviewed by Evan Brooks, Data Editor

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.