How do your marijuana plants grow in a hydroponics system? Easy. You put each plant in a pot with soilless medium and submerge its roots in a nutrient-rich solution. But there’s more. You would also need to make sure that each plant develops a healthy, extensive root system. You would also need to take care of the pH level, ensuring optimal absorption. Anything you need to know, all you have to do is to fire up the questions.