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by Matt Lollar, UF/IFAS Extension

Petiole sap testing is an educational tool andservice provided by the University of Florida/IFASExtension. By using portable meters, extensionagents provide vegetable farmers with informationon the current nitrogen and potassium nutrientstatus of their crop, delivering immediate analysis.This information allows farmers to identifywhether their crop nutrient status is low,adequate, or high without having to wait forresults from a lab. Research has shown that petiolesap is more sensitive to nitrogen rate changes thanleaf tissue analysis.