Fertilizers are responsible for over half of global food production, but there are areas in world with nutrient deficiency and other areas of nutrient excess.
Managing mineral plant nutrients requires careful application of science and skill to meet production, environmental, and social goals.
Langbeinite is a unique source of
plant nutrition since three essential nutrients are naturally combined into one
mineral. It provides a readily available supply of K, Mg, and S to growing
Langbeinite is a distinctive
geological material found in only a few locations in the world. Commercial
supplies of langbeinite come from underground mines near Carlsbad, New Mexico
(USA), which were first commercially developed in the 1930s. These deposits
were formed millions of years ago when a variety of salts, including
langbeinite, were left behind after the evaporation of ancient ocean beds.
These salt deposits were buried deep beneath hundreds of meters of sediment.
The langbeinite deposit is currently mined with large boring machines, washed
to remove impurities, and then crushed to various particle sizes. Langbeinite
is considered a potash (or K-containing) fertilizer, even though it also
contains valuable Mg and S. Traces of iron oxide impurities give some
langbeinite particles a reddish tint.
Underground mining in New Mexico
analysis: 21 to 22% K2O
solubility (20 ºC) 240 g/L
Langbeinite is a popular fertilizer, especially where
several nutrients are needed to provide adequate plant nutrition. It has an
advantage of having K, Mg, and S all contained within a single particle, which
helps provide a uniform distribution of nutrients when it is spread in the
field. Due to economics, langbeinite may not be recommended to meet the entire
K requirement of a crop. Instead, application rate may be based on the need for
Mg and/or S.
Langbeinite is totally water soluble, but is slower
to dissolve than some other common K fertilizers because the particles are
denser than other K sources. Therefore, it is not suitable for dissolving and
application through irrigation systems unless finely ground. It has a neutral
pH, and does not contribute to soil acidity or alkalinity. This differs from
other common sources of Mg (such as dolomite) which will increase soil pH and
from elemental S or ammonium sulfate which will lower the soil pH.
It is frequently used in situations where a
fertilizer free of Cl- is desirable, such as with crops sensitive to Cl- (some vegetables and
certain tree crops). Langbeinite is a nutrient-dense fertilizer with a
relatively low overall salt index. Particular sources of langbeinite have been
certified for use in organic crop production in some countries.
Langbeinite has no restrictions for environmental or
nutritional use when used at typical agronomic rates. One form of langbeinite
is sold as a feed grade dietary source of K, Mg, and S for animals and poultry.
All three of these nutrients are required for animal nutrition and each has a
specific metabolic role required for optimal animal health. This feed material
is “recognized as safe” by government agencies. As with all plant nutrients,
best management practices should be observed to properly utilize this resource.
A particular particle size should be matched with the specific need.
Most potash fertilizers are extracted from great depths
There are no major industrial
applications for langbeinite outside of agriculture.
Some examples of commercial langbeinite fertilizers produced in North America include the products of K-Mag (Mosaic Co), and TRIO (Interpid Potash).