MAX SET® 31 is designed primarily for foliar applications to prevent or correct phosphate and potassium deficiencies in a wide range of agronomic and ornamental plants. Its use is suggested as a supplement to a regular, balanced fertilizer program to enhance yields and improve quality. Application of MAX SET 31 is a means of obtaining a quick response to needed elements. Foliar applications of MAX SET 31 may be particularly beneficial during periods of peak nutrient demand, for crops grown on soils having poor nutrient availability or to crops suffering from a weakened root system. *Phosphorous acid products are intended to be used as a supplemental fertilizer treatment. MAX SET 31 contains the equivalent of 35.70% phosphorous acid, 31.00% phosphorous acid as P2O5, and 13.50% phosphorous acid as P. Upon foliar application, the phosphite ions are taken up directly by the plant foliage and may undergo a degree of conversion to phosphate ions or are utilized directly by plants as phosphite ions. As a soil application to annual crops, a lesser response from the initial crop with a corresponding superior response from succeeding crops may be observed. In addition, placement close to seeds or root zones may be injurious to crops. The effect may be aggravated by a soil pH below 6.5. MAX SET 31 should be used as part of a comprehensive Total Nutrition System® for optimizing plant growth, development, yield and quality.