Tiger 90CR Sulphur Bentonite Tiger 90CR® Sulphur Boosts Crop Performance Specifically formulated Tiger 90CR sulphur fertilizer (0-0-0-90) is designed to quickly degrade, disperse and convert to sulphate throughout the growing season. Research shows that Tiger 90CR sulphur converts to sulphate faster than other forms of elemental sulphur for season-long nutrition and high yields. Yearly applications of Tiger 90CR will improve soil sulphur levels and loss associated with soluble nutrients.