An agricultural gas wand system for distributing gas to a plant set including at least two supports adapted to be place adjacent the plant set, at least one elongated gas wand that engages two supports so that it is supported, adjustably with respect to height, adjacent the plant set, the at least one gas emission wand having a tubular body with a gas transmission lumen and at least one gas emitter element disposed on or in the body for egress of gas from the gas transmission lumen to the environment adjacent the plant set. Also disclosed is an agricultural gas canopy system including an elongated vertical support placed in close proximity to the plant set, and emitter array selectively coupleable to the support so that it is supported, adjustably with respect to height, above the plant. Also disclosed is a mobile gas canopy system for distributing gas to plants growing in rows including a movable gas canopy for enclosing a row of plants and along a length of the row, the canopy having a height which is greater than the height of the plants and a predetermined width which is greater than the width of the row defining an interior space for enclosing the plants, the canopy having an entrance end and an exit end which permit movement of the canopy along the row, and a gas supply for adding gas to the interior space.
