With Hydroponics, it is essential that the plants are able to access all the necessary nutrients needed to grow and be healthy. These are the elements needed, as well as a description of there functions to the plants. Carbon, hydrogen and oxygen are absorbed from the air and water. The rest of the elements, called mineral nutrients, are dissolved in the nutrient solution.

Nutrients are fertilizer or plant food. Since we have taken soil away we need to provide what soil would. They make all kinds and types of nutrients organic, synthetic, powder, liquid, 1 part 2 part and many more. Nutrients are the basis of any hydroponic system and since we need to meet all of the plants nutritional requirements, it’s important to know what you are supplying and what can go wrong. With any nutrient solution the two factors to keep in mind are firstly the composition of your nutrient – does it contain all of the elements required for plant growth in the correct ratios.

Nutrients are one of the basics of any hydroponic system. In order for a fertilizer to be incorporated into a hydroponic system it must be soluble in water. If not, the plant cannot access it. With Hydroponics the grower has complete control over the implementation of fertilizer, regarding type and concentration. They also have the ability to immediately monitor and maintain a relative consistency, provided a nutrient meter is available. The composition of the nutrients is important and there are over twenty elements that are needed for a plant to grow. Carbon, hydrogen and oxygen are absorbed from the air and water.

The rest of the elements, called mineral nutrients, are dissolved in the nutrient solution and need to be in the correct ratios. Any good Hydroponic nutrient should contain all of these elements;

  • Nitrogen (N),
  • Potassium (K),
  • Phosphorous (P),
  • Calcium (Ca),
  • Magnesium (Mg),
  • Sulphur (S),
  • Iron (Fe),
  • Manganese (Mn),
  • Copper (Cu),
  • Zinc (Zn),
  • Molydenum (Mo),
  • Boron (B),
  • Chlorine (Cl).

[Nitrogen/Phosphorus/Potassium] are the main “macronutrients” and all other nutrients/supplements [Cal/Mag, etc.] are considered “micronutrients”.

For the most part, this is taken care of with any pre-formulated commercial hydroponic nutrients. Often, these pre-made nutrients come in 1, 2, 3, or even more “parts” so the grower can change the ratio of the mineral elements to allow for either vegetative or fruiting and flowering growth, or for different crops. It is best for the beginner to just fallow the general directions before experimenting with changing the ratios.

With Hydroponics there is no soil to get the elements from, so the two are very different in composition because they are not designed to be a complete plant food and they may not water-soluble. For example, Nitrogen in the form of urea is not immediately available to a plant in hydroponics because urea is not soluble in water. For this reason Nitrogen must be delivered in its Nitrate form in order to be utilized in hydroponics.