Abstract: Apparatus for aeroponic growth and development of a multiplicity of plants comprising at least one plant development unit including at least one perforate plant support member adapted to secure plants above the root portions thereof and thereby to directly expose substantially all of the root portions thereof to the atmosphere; spraying apparatus for providing a nutrient mist directly to the exposed root portions of the plants; and nutrient collection and recirculation means; and control means for determining the timing of mist provision.