A light projector assembly for irradiating the interior of a bin when the bin is in a predetermined position, the bin having walls and a ceiling. A bin interior may include a plant-growing zone proximate a bottom of the bin. The walls may include one or more light-transmissive windows above the plant-growing zone. The light projector assembly may comprise a light projector and a support structure. A light projector may be supported outside of the bin position and proximate to and spaced from one of the one or more windows when the bin assembly is in the predetermined position. The light projector may be configured to project light upwardly through the one window and toward the ceiling. A support structure may support the light projector. The support structure may be spaced from a vertical extension of the predetermined position, unobstructive of vertical access to the bin.