Soil pH in Haskell, OK: Lime or Sulfur?

Typical topsoil pH in Haskell, OK

Typical topsoil in Haskell, OK is pH 5.5, too acidic for vegetable garden. Expect roughly 7 lb of lime per 100 sq ft, but only after a soil test confirms it.

What Haskell needs, by plant

• Already in range: potatoes, strawberries, blueberries, azaleas and rhododendrons, blue hydrangeas.
• Lime: lawn (cool-season grass) 7 lb/100 sq ft over 2 applications; vegetable garden 7 lb/100 sq ft over 2 applications; tomatoes 7 lb/100 sq ft over 2 applications; roses 7 lb/100 sq ft over 2 applications; pink hydrangeas 5.6 lb/100 sq ft over 2 applications.

What to do next

If your test confirms pH near 5.5, spread about 70 lb of ground limestone per 1,000 sq ft of vegetable bed in 2 doses, ideally in fall.

How mixed the soil is

Of the 365,432 surveyed acres in Haskell, OK, 51% are strongly acidic (below 5.5), 44% are moderately acidic (5.5-6.5), 4% are near neutral (6.5-7.3), 1% are alkaline (above 7.3). Mapped soils run from pH 4.6 to 7.9, a spread of 3.3 units across 151 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 16.4% 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. 1% of mapped components carry free carbonate (lime already in the ground).

Haskell against the rest of Oklahoma

pH 5.5 is 1.05 below the Oklahoma median of 6.55. 4 of 77 Oklahoma counties have more acidic topsoil. Nationally it is more acidic than the US county median of 6.05.

Closest in pH within the state: Adair (5.12), Delaware (5.14), Cherokee (5.2), Latimer (5.47), Le Flore (5.54), Pushmataha (5.55), McCurtain (5.59), Mayes (5.63).

The range in Oklahoma runs from Adair at 5.12 to Beaver at 7.65; Haskell sits 15% of the way up.