Hydroponics was the process of growing plants without soil.
Tarron had no native trees, so the human colony there had to grow them hydroponically. (PROSE: Tarnished Image)
Before most of the population of Mondas had been converted to Cybermen, the humans living there had a hydroponics centre, which contained the only living plants on the planet. (AUDIO: Spare Parts)
The TARDIS landed in the cargo hold of the Hyperion III, next to the hydroponics centre where the Vervoid pods were stored. (TV: Terror of the Vervoids)
After the Dione-Kisumu Company left Yemaya 4, LEONARDO stayed with the colony there and helped monitor their hydroponics. (PROSE: Sleepy)
The food on the Joseph Conrad was produced hydroponically. (PROSE: So Vile a Sin)
In Hope on Endpoint, Silver used hydroponics to grow plants. (PROSE: Hope)