A method of desiccating an environment surrounding a moisture-sensitive electronic device sealed within an enclosure, includes selecting a desiccant comprised of solid particles having a particle size range 0.1 to 200 micrometers, the desiccant selected to provide an equilibrium minimum humidity level lower than a humidity level to which the device is sensitive within the sealed enclosure; choosing a binder that maintains or enhances the moisture absorption rate of the desiccant for blending the selected desiccant therein, the binder being in liquid phase or dissolved in a liquid; forming a castable blend including at least the desiccant particles and the binder, the blend having a preferred weight fraction of the desiccant particles in the blend in a range of 10% to 90%; casting a measured amount of the blend onto a portion of an interior surface of an enclosure to form a desiccant layer thereover, the enclosure having a sealing flange; solidifying the desiccant layer to a solid; and sealing the electronic device with the enclosure along the sealing flange.