Soil pH in Oldham, KY: Lime or Sulfur?

Typical topsoil pH in Oldham, KY

Typical topsoil in Oldham, KY is pH 5.89, just outside the 6-7 range for vegetable garden. Test first; it may need nothing.

What Oldham needs, by plant

• Already in range: potatoes, strawberries, azaleas and rhododendrons.
• Just outside, test first: lawn (cool-season grass) (off by 0.1), vegetable garden (off by 0.1), roses (off by 0.1), pink hydrangeas (off by 0.1).
• Lime: tomatoes 4.2 lb/100 sq ft.
• Sulfur: blueberries 2.1 lb/100 sq ft over 2 applications; blue hydrangeas 1.4 lb/100 sq ft.

What to do next

If your test lands near 5.89, you can skip lime and sulfur for lawn (cool-season grass), vegetable garden, potatoes, strawberries, roses, azaleas and rhododendrons, pink hydrangeas.

How mixed the soil is

Of the 114,420 surveyed acres in Oldham, KY, 75% are moderately acidic (5.5-6.5), 18% are near neutral (6.5-7.3), 5% are strongly acidic (below 5.5), 2% are alkaline (above 7.3). Mapped soils run from pH 4.6 to 7.9, a spread of 3.3 units across 112 soil components. 75% of the land falls in one class, so the county figure is a fair first guess for most yards here.

Clay, organic matter and rates

Topsoil here averages 20.7% clay and 2.47% 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. 2% of mapped components carry free carbonate (lime already in the ground).

Oldham against the rest of Kentucky

pH 5.89 is 0.1 above the Kentucky median of 5.79. 68 of 120 Kentucky counties have more acidic topsoil. Nationally it is more acidic than the US county median of 6.05.

Closest in pH within the state: Todd (5.84), Casey (5.85), Livingston (5.85), Cumberland (5.89), Lincoln (5.91), Perry (5.91), Barren (5.92), Daviess (5.92).

The range in Kentucky runs from Greenup at 5.09 to Carroll at 6.63; Oldham sits 52% of the way up.