Synopsis An evaluation of the effects of 3 types of solution‐modifying agents‐evaporation‐retardant, surfactant, and osmotic agent‐on the growth of Kentucky bluegrass in nutrient solutions was made. Variations in osmotic pressure and surface tension of nutrient solutions affected turfgrass production. Increasing osmotic pressure decreased growth of foliage and increased root development. Decreasing surface tension decreased growth of foliage. An evapo‐retardant added to nutrient solutions had little effect on either osmotic pressure or surface tension but increased yields of foliage.