In 2151, a Kantare supply ship had an airponics bay, where the crew grew lorella. Malcolm Reed and Travis Mayweather became suspicious of the ship's occupants when they determined that the bay was in no way big enough to supply all the people living on it with food. (ENT: "Oasis")
A cargo bay on the USS Voyager was converted for use as a practical airponics garden. In the vernacular of the crew of Voyager, the space was sometimes simply called "airponics", muddying the lines between the bay itself and the scientific discipline. According to visual evidence, not all plants in the room were grown airponically, suggesting that the term "hydroponic bay" may have been equally applicable.
While presumably many Federation vessels had alternative cultivation facilities on board, Voyager had not been so equipped at launch, and therefore had to retrofit an existing space for the purpose. (VOY: "Parallax")
It was created and maintained primarily by Kes. Her main goal in its creation was to provide edible vegetation that might alleviate the drain on energy resources caused by replicating food. She became so attached to the space that, when pressed by the Ocampan Tanis to take him to "the place that is special to you," she chose to introduce him to the airponics bay. (VOY: "Cold Fire") Kes' departure, however, did not force the closure of the bay. At least one other crewman, Doug Bronowski, also pulled duty shifts there, after Kes left. (VOY: "Someone to Watch Over Me")
In 2371, suspicious of Tom Paris's attentions towards Kes, Neelix asked her if Paris was going to be helping her in the airponics bay later, as he had departed her presence promising to see her later. (VOY: "Elogium")
In 2372, Paris selected three flower specimens from the airponics bay (a chrysanthemum, a clematis, and a symbiogenetic orchid) so that Voyager's crew could perform a transporter experiment to join the three plants together in order to determine how to split Tuvix into Tuvok and Neelix again. All tests were unsuccessful. (VOY: "Tuvix")
In 2373, Kes promised to show visiting Ilari Nori and Adin the airponics bay. Neelix invited her to go sailing with him, but she explained that she already had plans. Later, while fighting Tieran's takeover of her body, Kes reasserted herself when she mentioned some of her happiest moments were watching her seedlings grow there. (VOY: "Warlord")
In 2375, B'Elanna Torres, needing room to work in main engineering, asked Seven of Nine, who was showing One around USS Voyager per Kathryn Janeway's request, to familiarize the Borg drone with Voyager's airponics bay instead. (VOY: "Drone")
Later that year, when Naomi Wildman decided she ought to have duties like everyone else on Voyager, Neelix suggested the airponics bay could use some help. Naomi was more interested in working on the bridge, however. (VOY: "Once Upon a Time")
Later on, Naomi was considering using vegetables grown in the airponics bay to make the tetragon Seven had assigned her to build with ordinary objects without using a replicator. She decided on carrots and celery. (VOY: "Memorial")
The location of the airponics bay is suggested by VOY: "Parallax". In the episode, Kes tells Captain Janeway that she believes energy reserves could be stretched by the creation of a hydroponics bay. Harry Kim notes that "cargo bay 2" could easily be converted to that purpose, because of its specialized environmental control. Although the term "hydroponic" is rarely used afterwards, some of the plants seen in the "airponic bay" do appear to be growing non-airponically. As seen in the picture at top right, the plants on the lower level of each unit seem to have their roots growing in what appears to be a thin layer of soil – a marked contrast to how the plants are growing on the first two tiers. Given that Kes requested nitrogenated soil to start her "hydroponics bay" in "Parallax", it is reasonable to assume that the "hydroponics bay" of "Parallax" and the "airponics bay" of much of the remainder of the series are the same area.
"Cargo bay 2" is an area referred to in the series in widely differing ways. "Parallax", as discussed above, suggests that it is the home of the hydroponic/airponic bay. However, VOY: "Maneuvers" places it as the site of a deliberate Kazon shuttle crash. In this episode, it is stated that "cargo bay 2" is on deck 4, close to a transporter room. This "cargo bay 2" is probably not the same one in which Kes gardened, as there is no sign of the plants that were seen in airponics in the previous episode, "Cold Fire". Later in the series, the Borg assimilate "cargo bay 2", which eventually becomes the site of Seven of Nine's alcove. (VOY: "Scorpion, Part II") The "Equinox" two-parter places that alcove firmly on deck 8. Thus, if Kes did take Harry Kim's suggestion and build her garden in "cargo bay 2", other, conflicting uses of the term have made it difficult to establish exactly where her "cargo bay 2" is.
It is unclear whether similar areas on other starships were actually called "airponic (or hydroponic) bays", as the name was first suggested by Kes in a way that implied the combination of the term "cargo bay" with the space's new purpose. However, the crew's ready acceptance of the term may counter-suggest that it was a perfectly acceptable "Starfleet term" in wide use.
The units in the airponics bay were reused from Star Trek VI: The Undiscovered Country, in which they appeared as crew bunks. (text commentary, Star Trek VI: The Undiscovered Country (Special Edition) DVD)