Soil pH in Waldo, ME: Lime or Sulfur?

Typical topsoil pH in Waldo, ME

Typical topsoil in Waldo, ME is pH 4.72, too acidic for vegetable garden. Expect roughly 12.6 lb of lime per 100 sq ft, but only after a soil test confirms it.

What Waldo needs, by plant

• Already in range: blueberries, azaleas and rhododendrons.
• Lime: lawn (cool-season grass) 12.6 lb/100 sq ft over 3 applications; vegetable garden 12.6 lb/100 sq ft over 3 applications; tomatoes 12.6 lb/100 sq ft over 3 applications; potatoes 5.6 lb/100 sq ft over 2 applications; strawberries 9.1 lb/100 sq ft over 2 applications; roses 12.6 lb/100 sq ft over 3 applications; blue hydrangeas 3.5 lb/100 sq ft; pink hydrangeas 10.5 lb/100 sq ft over 3 applications.

What to do next

If your test confirms pH near 4.72, spread about 126 lb of ground limestone per 1,000 sq ft of vegetable bed in 3 doses, ideally in fall.

How mixed the soil is

Of the 427,583 surveyed acres in Waldo, ME, 96% are strongly acidic (below 5.5), 4% are moderately acidic (5.5-6.5). Mapped soils run from pH 3.9 to 7.8, a spread of 3.9 units across 436 soil components. 96% 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 8.7% clay and 7.8% organic matter, which this site treats as loam. At 7.8% organic matter the soil buffers like a heavier one, which pushes it into the loam bracket. Moving it one pH unit takes about 7 lb of lime or 2.3 lb of sulfur per 100 sq ft. None of the mapped components carry free carbonate.

Waldo against the rest of Maine

pH 4.72 is 0.16 below the Maine median of 4.88. 4 of 16 Maine counties have more acidic topsoil. Nationally it is more acidic than the US county median of 6.05.

Closest in pH within the state: Piscataquis (4.59), Somerset (4.64), Oxford (4.68), Franklin (4.69), Knox (4.78), Aroostook (4.8), Hancock (4.88), York (4.88).

The range in Maine runs from Piscataquis at 4.59 to Cumberland at 5.01; Waldo sits 31% of the way up.