All plants have the same basic needs of light, carbon dioxide (CO₂), oxygen, water, heat and food in the form of nutrients. These nutrients only make up approximately 2% of the mass of the plant, which it cannot synthesise for itself from carbon dioxide and water. Photosynthesis is the process by which plants turn CO₂ and water into organic compounds, primarily sugars:
If plants are not given enough of all of these essential elements, then it can have a detrimental effect on their growing. Different plants require these elements in differing ratios, but they are all needed whether the plant is in the soil or grown hydroponically.
When you grow hydroponically, you can control and enhance all of a plant’s basic needs and you even have the ability to ensure adequate oxygen is available to the roots.