This paper presents the dielectric behaviour of suspensions of tomato cells (MSK8) and tobacco cells (BY2) in Murashige and Skoog, and Phosphate Buffer solutions. The behaviour of various concentrations of such suspensions is studied over a wide range of frequencies (1 kHz to 20 GHz). A distinct trend is observed in the relation between cell concentration and the capacitance of the first dispersion (i.e. at low frequencies), whilst the capacitance of the second dispersion (at medium frequencies) shows a clear relationship with the medium used. As the concentration of the cells increases, the capacitance observed increases for both cell types in both media. Furthermore, the capacitance observed for the MSK8 cells is higher than that for the BY2 cells in both media; furthermore, the normalized impedance magnitude of the MSK8 cell suspensions at low frequencies is higher than that of the equivalent normalized impedance magnitude for BY2 cells. Finally, the capacitance corresponding to the second dispersion is higher in Phosphate Buffer solution compared to that in Murashige and Skoog solution.