Soil pH in Concordia, LA: Lime or Sulfur?

Typical topsoil pH in Concordia, LA

Typical topsoil in Concordia, LA is pH 6.11, already right for vegetable garden (6-7). Test before adding anything.

What Concordia needs, by plant

• Already in range: lawn (cool-season grass), vegetable garden, strawberries, roses, pink hydrangeas.
• Just outside, test first: tomatoes (off by 0.1), potatoes (off by 0.1), azaleas and rhododendrons (off by 0.1).
• Sulfur: blueberries 3.7 lb/100 sq ft over 2 applications; blue hydrangeas 3.1 lb/100 sq ft over 2 applications.

What to do next

If your test lands near 6.11, you can skip lime and sulfur for lawn (cool-season grass), vegetable garden, tomatoes, potatoes, strawberries, roses, azaleas and rhododendrons, pink hydrangeas.

How mixed the soil is

Of the 378,515 surveyed acres in Concordia, LA, 43% are near neutral (6.5-7.3), 42% are moderately acidic (5.5-6.5), 15% are strongly acidic (below 5.5). Mapped soils run from pH 5.3 to 7.3, a spread of 2 units across 73 soil components. No single class covers 60% of the county, so two gardens a few miles apart here can need opposite treatments. Test your own bed.

Clay, organic matter and rates

Topsoil here averages 48.7% clay and 2.3% organic matter, which this site treats as clay. Moving it one pH unit takes about 11.5 lb of lime or 3.4 lb of sulfur per 100 sq ft. 0% of mapped components carry free carbonate (lime already in the ground).

Concordia against the rest of Louisiana

pH 6.11 is 0.57 above the Louisiana median of 5.54. 42 of 64 Louisiana counties have more acidic topsoil. Nationally it is more alkaline than the US county median of 6.05.

Closest in pH within the state: Natchitoches (5.77), Madison (5.82), East Carroll (6.01), Red River (6.04), Vermilion (6.15), Cameron (6.16), St. Landry (6.16), Lafourche (6.28).

The range in Louisiana runs from Allen at 4.88 to St. Bernard at 7; Concordia sits 58% of the way up.