Soil pH in Matanuska-Susitna Borough, AK: Lime or Sulfur?
Typical topsoil pH in Matanuska-Susitna Borough, AK
Typical topsoil in Matanuska-Susitna Borough, AK is pH 5.2, too acidic for vegetable garden. Expect roughly 9.1 lb of lime per 100 sq ft, but only after a soil test confirms it.
What Matanuska-Susitna Borough needs, by plant
- Already in range: potatoes, blueberries, azaleas and rhododendrons, blue hydrangeas.
- Lime: lawn (cool-season grass) 9.1 lb/100 sq ft over 2 applications; vegetable garden 9.1 lb/100 sq ft over 2 applications; tomatoes 9.1 lb/100 sq ft over 2 applications; strawberries 5.6 lb/100 sq ft over 2 applications; roses 9.1 lb/100 sq ft over 2 applications; pink hydrangeas 7 lb/100 sq ft over 2 applications.
What to do next
If your test confirms pH near 5.2, spread about 91 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 2,172 surveyed acres in Matanuska-Susitna Borough, AK, 100% are strongly acidic (below 5.5). Mapped soils run from pH 4.6 to 5.3, a spread of 0.7 units across 4 soil components. 100% 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 9.4% clay and 7.59% organic matter, which this site treats as loam. At 7.59% 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.
Matanuska-Susitna Borough against the rest of Alaska
pH 5.2 is 0.06 below the Alaska median of 5.26. 11 of 27 Alaska counties have more acidic topsoil. Nationally it is more acidic than the US county median of 6.05.
Closest in pH within the state: Kodiak Island Borough (4.96), Kusilvak Census Area (old Wade Hampton) (5.04), Haines Borough (5.1), Valdez-Cordova Census Area (5.15), Northwest Arctic Borough (5.23), Kusilvak Census Area (5.26), Juneau Borough (5.3), Petersburg Borough (5.3).
The range in Alaska runs from Ketchikan Gateway Borough at 4.52 to Yakutat City and Borough at 6.08; Matanuska-Susitna Borough sits 44% of the way up.