The invention is an automated sprayer for spraying the walls of a bath and shower enclosure with a cleanser. The sprayer has a housing that can be mounted inside the shower enclosure and that defines a tray in which an inverted bottle of cleanser is stored. The bottom of the tray has a tube extending downwardly along a longitudinal axis through which the cleanser can pass. A motorized head disposed beneath the tube can be rotated about the axis for metering cleanser from the bottle and spraying cleanser outward. The sprayer includes timer circuitry that delays commencement of a spray for a set time and automatically stops spraying after a predetermined period. The sprayer also includes a system for signaling the beginning of a spray cycle including audio and visual alarms. An automated method of cleaning the shower enclosure is also disclosed.