In a study of the dry matter produced by limiting one so-called "essential" nutrient, it was found that the nitrate ion affected most the yield of dry matter per milligram of NO3. About twice the yield per mgm. was made with an economic addition of nitrate as compared with other important fertilizer constituents, such as phosphate and potassium. The formation of dry matter per mgm. of Mg ion furnished is comparatively low for the conditions of the experiment. The greatest economic growth of alfalfa plants occurred with the addition of about 2 parts per million of phosphate, Mg, and K. A greater relative concentration of Ca than of other "essential" nutrients is necessary for substantial growth, and this continues up to approximately 30 parts per million. There was a substantial increase from 8 to 16 parts of sulphate. A larger container or smaller number of plants might have indicated even lower results.