The nutrients used in hydroponic gardening are combined in ideal quantities for different types of plants. Nutrients are basically divided into two categories, macronutrients and micronutrients
Nitrogen. Nitrogen is a major part of many amino acids and is important to all of them. Nitrogen is a major element in most plant fertilizers. In hydroponic nutrient mixtures the nitrogen is readily extracted by plants and eases the energy demands.
Phosphorus. Phosphorus is essential for the formation of cell walls and is a major constituent of commercial fertilizers. The lack of phosphorus in soil is a common cause of stunted an ill formed vegetation.
Potassium. Living cells cannot function without potassium and plant cells have a particularly high concentration. Fruits are an excellent source of potassium for humans and animals.
Calcium. Calcium is a major instigator of cellular activity. It has a significant affect upon growth rates. Although reasonably available from most soil types, calcium does require a high-energy consumption to extract it efficiently. This energy can be turned towards growth in hydroponics.
Magnesium. Magnesium is a central component of chlorophyll without which most plant life cannot survive. Generally magnesium is plentiful in most soils although in magnesium poor soils plants tend to be weakly and yellow.
Sulfur. Sulfur is one of the essential elements and is found in amino acids.
Silicon. Silicon has a direct effect upon the metabolism of plants and is essential to their well being. As a major facilitator of several processes within plant cells, silicon has a direct effect upon growth.
Micronutrients are usually found at trace levels but are still essential to life. They include:
- Nickel Molybdenum
Boron. Boron is a tricky element in that, while it is essential in trace amounts, plants can only tolerate it in extremely low limits.
Oxygen, Carbon and Hydrogen. Large amounts of oxygen, carbon and hydrogen are necessary to plants and most life forms on Earth. These elements are not really classed as nutrients even though they do have a significant effect upon plants and animals to survive. The metabolism of most living organisms is directly affected by the presence or lack of any of these elements. In hydroponics they are often added to the nutrient solutions by the infusion of air.
A well-formulated nutrition mix for hydroponic gardens will include all the essential food types. For effective and rapid absorption they will be in soluble form. They are able to move freely throughout a system and be immediately available to any root system. Although adding oxygen, hydrogen and carbon to the food mix is beneficial to the plants, adding it to any of the nutrients could upset and damage the plants.
Knowing the benefits of the elements that make up the hydroponic nutrient mix can help identify problems if they arise. Yellowing leaves, for example, could indicate a magnesium deficiency. This deficiency could be caused by a systemic disease or by the accidental introduction of weed killer.