Plant tissue analysis is a chemical analysis of plant leaves and other organs. Generally, a higher availability of a nutrient in the soil translates into a greater concentration of that nutrient in the plant. However, the availability of a certain nutrient in the soil is not the only factor affecting its uptake by the plant. Other factors, such as temperature, humidity, soil moisture, plant diseases etc., considerably affect the uptake of nutrients. Plant analysis reflects both nutrient availability in the soil and the nutritional status of the plant. 

The concentration of nutrients in the plant is not fixed, but constantly changes. It may vary from month to month and even from day to day. The concentration of nutrients even differs between various parts of the same plant. In order to learn the rate in which a nutrient is absorbed, it is necessary to take samples from several plant parts at different growth stages. 

The most common uses of plant analysis are verification of visual growth problems and identification of nutrient deficiencies or excess.