Abstract <p>A laboratory technique has been developed to study the effect of dissolved substances on the condensational growth of spherical droplets of water in a self-arranged droplet cluster levitating above a locally heated water surface, as well as on the equilibrium droplet size obtained by infrared heating of the cluster. Inorganic salts such as potassium and sodium chlorides were shown to significantly influence the condensation/evaporation process of water droplets even at low solute concentrations. In contrast, the influence of typical substances used in plant treatments is negligible. The new experimental results can be used to model various technological processes involving aqueous aerosols. These results might also be useful in studies of moisture transfer and precipitation formation in the atmosphere.</p>