Soil pH in Llano, TX: Lime or Sulfur?

Typical topsoil pH in Llano, TX

Typical topsoil in Llano, TX is pH 6.68, already right for vegetable garden (6-7). Test before adding anything.

What Llano needs, by plant

• Already in range: lawn (cool-season grass), vegetable garden, tomatoes, roses.
• Just outside, test first: strawberries (off by 0.2), pink hydrangeas (off by 0.2).
• Sulfur: potatoes 2.8 lb/100 sq ft over 2 applications; blueberries 3.9 lb/100 sq ft over 2 applications; azaleas and rhododendrons 3.2 lb/100 sq ft over 2 applications; blue hydrangeas 3.2 lb/100 sq ft over 2 applications.

What to do next

If your test lands near 6.68, you can skip lime and sulfur for lawn (cool-season grass), vegetable garden, tomatoes, strawberries, roses, pink hydrangeas.

How mixed the soil is

Of the 515,551 surveyed acres in Llano, TX, 58% are near neutral (6.5-7.3), 34% are moderately acidic (5.5-6.5), 8% are alkaline (above 7.3). Mapped soils run from pH 5.9 to 8.2, a spread of 2.3 units across 49 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 14.5% clay and 1.53% organic matter, which this site treats as loam. Moving it one pH unit takes about 7 lb of lime or 2.3 lb of sulfur per 100 sq ft. 10% of mapped components carry free carbonate (lime already in the ground).

Llano against the rest of Texas

pH 6.68 is 0.75 below the Texas median of 7.43. 58 of 254 Texas counties have more acidic topsoil. Nationally it is more alkaline than the US county median of 6.05.

Closest in pH within the state: Wharton (6.54), Brooks (6.62), Matagorda (6.62), Lamar (6.68), Gonzales (6.7), Fort Bend (6.71), Lavaca (6.71), Limestone (6.73).

The range in Texas runs from Hardin at 4.64 to Upton at 8.19; Llano sits 57% of the way up.