Apr 10
19
Nutrient disorders are caused by too much or too little of one or
several nutrients being available These nutrients are made available
between a pH range of 5 and 7 and a total dissolved solids (TDS) range
of 800 to 3000 PPM. Maintaining these conditions is the key to proper
nutrient uptake.
Over twenty elements 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. The primary or macro- nutrients (nitrogen (N), phosphorus
(P) and potassium (K)) are the elements plants use the most. Calcium
(Ca) and magnesium (Mg) are secondary nutrients and used in smaller
amounts. Iron (Fe), sulfur (S), manganese (Mn), boron (B), molybdenum
(Mo), zinc (Zn) and copper (Cu) are micro-nutrients or trace elements.
Trace elements are found in most soils. Rockwool (hydroponic)
fertilizers must contain these trace elements, as they do not normally
exist in sufficient quantities in rockwool or water. Other elements
also play a part in plant growth. Aluminum, chlorine, cobalt, iodine,
selenium, silicon, sodium and vanadium are not normally included in
nutrient mixes. They are required in very minute amounts that are
usually present as impurities in the water supply or mixed along with
other nutrients.
The above nutrients are mixed together to form a complete plant
fertilizer. The mix contains all the nutrients in the proper ratios to
give plants all they need for lush, rapid growth. The fertilizer is
dissolved in water to make a nutrient solution. Water transports these
soluble nutrients into contact with the plant roots. In the presence
of oxygen and water, the nutrients are absorbed through the root
