Soil pH in Tompkins, NY: Lime or Sulfur?

Typical topsoil pH in Tompkins, NY

Typical topsoil in Tompkins, NY is pH 5.99, just outside the 6-7 range for vegetable garden. Test first; it may need nothing.

What Tompkins needs, by plant

• Already in range: potatoes, strawberries, azaleas and rhododendrons.
• Just outside, test first: lawn (cool-season grass) (off by 0), vegetable garden (off by 0), tomatoes (off by 0.2), roses (off by 0), pink hydrangeas (off by 0).
• Sulfur: blueberries 3.4 lb/100 sq ft over 2 applications; blue hydrangeas 2.4 lb/100 sq ft over 2 applications.

What to do next

If your test lands near 5.99, 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 280,425 surveyed acres in Tompkins, NY, 61% are moderately acidic (5.5-6.5), 22% are near neutral (6.5-7.3), 17% are strongly acidic (below 5.5). Mapped soils run from pH 4.5 to 8, a spread of 3.5 units across 545 soil components. 61% 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 18.1% clay and 5.49% organic matter, which this site treats as clay. At 5.49% organic matter the soil buffers like a heavier one, which pushes it into the clay bracket. Moving it one pH unit takes about 11.5 lb of lime or 3.4 lb of sulfur per 100 sq ft. 4% of mapped components carry free carbonate (lime already in the ground).

Tompkins against the rest of New York

pH 5.99 is 0.22 above the New York median of 5.77. 41 of 62 New York counties have more acidic topsoil. Nationally it is more acidic than the US county median of 6.05.

Closest in pH within the state: Tioga (5.87), Broome (5.9), Schuyler (5.9), Wyoming (5.91), Erie (6.02), Yates (6.1), Wayne (6.13), Jefferson (6.16).

The range in New York runs from Hamilton at 4.72 to Kings at 7.15; Tompkins sits 52% of the way up.