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Marion County Soil Data

Marion County, Missouri

USDA SSURGO / PHZM

Avg pH

6.3

Texture

Silt Loam

Drainage

Subaqueous

Organic Matter

2.7%

Hydrologic Group

N/A

Data Story

About Soil in Marion County, Missouri

Healthy, High-Quality River Border Soils

Marion County boasts an average soil pH of 6.31, which is higher than the state average of 6.09. This puts it within the ideal range for many commercial crops and near the national 6.5 median. The county earns a high overall soil score of 73.8.

Fine-Textured Silt and Clay Mix

The soil is heavily weighted toward silt at 61.7%, with a 21.4% clay component. Sand makes up 17.0% of the profile, providing a fine-textured soil that holds nutrients well. This composition is typical of the productive lands found along the Mississippi River corridor.

Exceptional Available Water for Crops

The available water capacity is a robust 0.205 in/in, significantly higher than the Missouri average of 0.183 in/in. Organic matter is healthy at 2.67%, well above the 2.0% national average. These traits make the county highly resilient during Missouri's hot, dry summer months.

Managing Saturated Subaqueous Environments

Like many of its neighbors, Marion's dominant drainage class is listed as subaqueous. Hydrologic group data is not currently specified for the county's primary soil types. Users should anticipate high moisture levels and plan for adequate drainage in garden and field layouts.

Prime Zone 6a Growing Conditions

Marion County's Zone 6a climate is excellent for growing everything from apples to zucchini. The high water capacity of the soil is a major asset for producing juicy fruits and large vegetables. Get your seeds in the ground and take advantage of this high-scoring Missouri soil.

Soil Composition

Silt Loam
Sand: 17.0%
Silt: 61.7%
Clay: 21.4%
Silt Loam

Soil pH

6.3pH
6.31009113788605
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

Subaqueous

Drainage class: Subaqueous

Soil Profile

Dominant texture: Silt Loam

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.

Soil Amendment Products

Browse products to improve your soil health and lawn performance.

Browse Soil Amendments

Frequently Asked Questions

What type of soil does Marion County have?

Marion County's soil is classified as Silt Loam. This indicates the relative proportions of sand, silt, and clay — 17% sand, 62% silt, and 21% clay. Loamy soils hold moisture well and support a wide range of plants.

Is Marion County's soil acidic or alkaline?

Marion County's soil has a pH of 6.3, which is moderately acidic. This range suits many crops and is common across much of the eastern US.

What is the drainage class for Marion County?

Marion County has a dominant drainage class of "Subaqueous." Moderate drainage allows adequate moisture retention while still permitting excess water to drain over time.

What crops or plants grow well in Marion County's soil?

Based on Marion County's Silt Loam texture, pH of 6.3, and Subaqueous, the soil is well suited for vegetables, grains, and most field crops, row crops and vegetable gardens.

What USDA soil order is found in Marion County?

The dominant USDA soil order for Marion County is not currently available in our dataset.

Soil & Planting Advisory: Marion County

Soil Verdict

Marion County is in USDA hardiness zone 6a, a moderate climate zone. where winter lows can reach -10°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

Marion County closely matches the Missouri average hardiness conditions.

Other Counties in Missouri

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.