Whey as a Source of Plant Nutrients and Its Effect on the Soil

Abstract

The possibility of the use of whey as a source of plant nutrients was investigated through laboratory analysis and field studies. A ton of whey was found to contain about one dollar's worth of nitrogen, phosphorus, and potassium, plus significant amounts of sodium, calcium, magnesium, and chlorides. Whey applications do not have a detrimental effect on the pH of soils which are well limed and near neutral. However, whey added to soils with a pH of 5.0–5.5 may temporarily increase the soil acidity to a point which is injurious to plant growth. Alfalfa will tolerate a limited amount of whey but does not benefit much from it. About one-half acre inch per week is the maximum quantity tolerable. Grasses appear more tolerant, and whey applications increased the growth of bluegrass, especially during the second growing season. This delayed benefit seems due to the slow breakdown of nitrogen compounds in the whey. Whey benefits soil aggregation, with the amount of aggregation being dependent on the amount of whey added. However, exceedingly large applications may result in a reduction in the formation of aggregates. © 1959, American Dairy Science Association. All rights reserved.