The phytohormone extraction method is reproducible. (a) The abundance of the phytohormones ABA, JA, SA and the SA glycoside expressed as a ratio of the added internal standard. Standard error for the seven replicates is less than 10% of the mean value. Glycosylated derivatives can also be determined by ratioing relative to the unglycosylated internal standard. (b) Determination of the absolute value of phytohormones present in the stressed tissue demonstrates that this method can accurately capture the dynamic range of phytohormones with small amounts of starting material (10 mg).