Agriculture Reference
In-Depth Information
soil, don't worry. In addition, these concerns largely pertain to
inorganic fertilizers such as ammonium nitrate. When the
fertilizers are organic, and composed of such substances as
blood meal or alfalfa meal, the adverse effect of the lime is
considerably reduced.
Though excessively alkaline (e.g. a pH higher than 6.5) soils
are rare in the U.S., they exist in a few places such as the
Black Belt prairie region of Alabama, and can be accidentally
created through excessive liming.
Correcting an excessively alkaline soil can be done using a
variety of substances, including elemental sulfur (known as
flowers of sulfur), ammonium sulfate, sulfur coated urea and
ammonium nitrate. These substances are seen to be ideal in
industrial agriculture, but they are excessively concentrated
and can hurt the soil biology, so they aren't recommended for
a mini farm aiming at sustainability.
Some authorities also recommend aluminum sulfate, but the
levels of aluminum (if the pH ends up changing) can be taken
up by the plant and can become toxic to both plants and
animals. I recommend either straight flowers of sulfur (if
growing organically), or ammonium sulfate (if you don't mind
synthetic fertilizers). In practice, the amount of ammonium
sulfate required to lower soil pH a given amount is 6.9 times