Precise plant-tissue results are possible only when carefully selected plant material is submitted for analysis.
Accurate sampling requires that select parts of a plant are collected at certain stages of plant development.
A plant’s nutritional condition differs for each variety, stage of development and growing area. It is recommended to select plant tissue representative of a particular variety and growing area. Place samples in unlined paper bags.
If tissue sampling to troubleshoot problem areas, it is very helpful to sample not only the 'problem' areas, but also the 'normal' growth areas in the same field for comparison purposes. It is encouraged to pull representative soil samples at the same time as plant samples.
What Not to Sample: Diseased or dead plant material; plant tissue damaged by insects and/or mechanical equipment; plant tissue which has been stressed by excesses of cold, heat or moisture; seeds should NOT be sampled as they do not reflect nutritional status of the whole plant.