The present invention relates to an apparatus and a method for maximizing a yield by extending a harvest period of edible plants in a plant cultivation management device, which can extend the harvest period to be at least three times longer than a normal harvest period by preventing or inhibiting the bolting of edible plants in facilities or outdoors. The present apparatus for maximizing a yield by extending a harvest period of edible plants growing in a management device of a facility comprises: a plurality of plant cultivation management devices accommodating, up to a predetermined height from the bottom, a moisture-absorbing member including orchid stone, perlite and coarse sand, accommodating, up to the height of the moisture-absorbing member, water for supplying moisture to the moisture-absorbing member, and including a water-retaining member for separation and fertilizer-mixed soil, which are sequentially provided on the moisture-absorbing member a plurality of plant-growing pots fixed and arranged to be separated from each other at a required distance for plant-growing space in order to allow the plants to take root in the fertilizer-mixed soil of the plant cultivation management device, and moved in order to grow one of young seedlings and mature seedlings of the edible plants such that the edible plants can be harvested a plurality of supports, a pair of which are provided to be separated from each other in order to arrange the plant cultivation management devices at a height at which a manager or a worker can harvest the edible plants while standing, and which ensures an air circulation passage by aligning the plant cultivation management devices at predetermined intervals from each other an air duct provided so as to be long along an alignment direction of the plant cultivation management devices in the interval between the pair of supports, having air holes for individually supplying one type of wind, selected from cold air and hot air, toward the air ci
