Dry Fertilizers Containing Sulfate

A survey of sulfur (S)‐containing fertilizers in 1971 lists 16 dry and 5 fluid sources of S products. An understanding of the various factors affecting movement of SO4 2‐ and the transformations of S0 in soils is helpful in determining optimum methods and timing of S fertilization.

Sulphur is essential for many growth functions in plants including nitrogen metabolism, enzyme activity and protein and oil synthesis. Generally, sulphur-deficient plants have short and/or spindly stems and yellowing of the young (top) leaves. With nitrogen deficiency, yellowing affects the older, lower leaves first. Sulphur-deficient canola can also have purpling and upward cupping of young leaves, delayed and prolonged flowering, pale-coloured flowers and fewer, smaller pods.

Sulphur-deficient alfalfa, pea and other legumes may have reduced nitrogen fixation.

For cereals and forage grasses, yellowing of the newly-emerging leaves is an indicator of sulphur deficiency.