Hydroponic Nutrients Explained

Hydro Nutrient Basics:

Plants need large amounts of 6 macro-nutrients: Nitrogen (N), Phosphorus (P), and Potassium (K). The NPK numbers you see on a manure or fertilizer bag (like 30-10-30) are simply telling you at what ratio these three macro-nutrients are mixed in that bag of fertilizer. The other 3 macros are calcium, sulfur and magnesium. All 6 are provided in the proper ratio in all hydroponics solutions. Plants also need micro-nutrients (minute traces of other elements) in order to thrive, just like you do. The nutrient solutions for your garden are different from ordinary plant fertilizers. They include all the trace elements too.   These traces elements include iron, boron, manganese, zinc, molybdenum, copper, cobalt, chlorine, selenium and silicon.

Where do they come from?  Is it healthy?

Hydroponic nutrient is mineral salts (sodium).   Sodium is a ubiquitous element that exists pretty much everywhere.   It plays a key role in many biological processes.   When you buy soil, you are buying a mixture of organic material, with added minerals.  In the majority of cases, the minerals in the store bought soil, have come from the same manufacturers as the hydroponic minerals.   The manufacturer uses various base elements to form chemical compounds that are formed by the neutralization reaction of an acid and a base. For example, Calcium Nitrate is the most significant element in hydroponics.   (It’s basically Nitrogen or the ‘N’ of the PK.)   Calcium nitrate is a relatively simple salt to produce.   Manufacturers will basically take limestone and react it with dilute nitric acid.   The resulting reaction produces calcium nitrate. Magnesium Sulphate is another key component and is made by reacting magnesium oxide (normally found as mineral kieserite) with dilute sulfuric acid.

Hydroponic Nutrient Recipe Example:

Here is a list of many of the base incredients found in your hydroponic mineral salts: Vegetative Stage Nutrient Formulation
  • 6.00 grams – Ca (NO3) 2: Calcium Nitrate
  • 2.42 grams – MgSO4 * 7H2O: Magnesium Sulfate
  • 2.09 grams – KNO3: Potassium Nitrate
  • 1.39 grams – KH2PO4: Monopotassium Phosphate
  • 0.46 grams – K2SO4: Sulfate of Potash
  • 0.40 grams – 7% Fe Chelated Trace Elements – see below
Flowering Stage Nutrient Formula
  • 4.10 grams – Ca (NO3) 2: Calcium Nitrate
  • 2.40 grams – MgSO4 * 7H2O: Magnesium Sulfate
  • 2.80 grams – KNO3: Potassium Nitrate
  • 1.39 grams – KH2PO4: Monopotassium Phosphate
  • 0.46 grams – K2SO4: Sulfate of Potash
  • 0.40 grams – 7% Fe Chelated Trace Elements – see below
Fruiting Stage Nutrient Formula
  • 8.00 grams – Ca (NO3) 2: Calcium Nitrate
  • 2.80 grams – KNO3: Potassium Nitrate
  • 2.40 grams – MgSO4 * 7H2O: Magnesium Sulfate
  • 1.70 grams – K2SO4: Sulfate of Potash
  • 1.39 grams – KH2PO4: Monopotassium Phosphate
  • 0.40 grams – 7% Fe Chelated Trace Elements – see below
Chelated Trace Elements
  • 7.00%  Iron (Fe)
  • 2.00%  Manganese (Mn)
  • 1.30% Boron (B)
  • 0.40%  Zinc (Zn)
  • 0.10% Copper (Cu)
  • 0.06%  Molybdenum  (Mo)

So What?

So the difference between common fertilizers and hydroponic nutrient is that the nature of soil based minerals is slowly released whereas hydroponic minerals are fast release with fast up-take, thus optimal results & faster growth.   As hydroponic mineral salts are basically derived from base elements and then reacted to create a crystaline form of the chemical compounds necessary for plant growth, they cannot be deemed as ‘organic’. With the global adoption of hydroponic methods worldwide growing very fast…. like very fast!    Next time you walk through the vegetable aisle in your supermarket, you may be surprised to know that up to 50%+ of the produce is growin hydroponically!    So those concerned about potential health consiquences should consider where there veggies are coming from.   Growing your own veggies from home without the use of pesticides surely is a better way to go!   Alternatively just use the organic options instead. In our experience, we’ve found that growing hydroponically is very safe, effective and produces top quality with excellent flavour, hence we’ll continue to utilise hydroponics.  In essence, a plant doesn’t care where it gets its nutrients from, be it man-made, organic, or something you produce in your home. All they care about is that they receive all they need to grow to their full potential. Hydroponic Salts are any chemical compounds that can be formed by the neutralization reaction of an acid and a base, and when this is dissolved in water, it breaks up completely into ions. Once the ions are free in the solution, the plant root system does the work and takes them up for growth and reproduction.

A couple of weeks later

About the Author

Mr Stacky is the leader in Tower Garden Systems in Australia, specializing in commercial hydroponic farming, urban farming & residential vertical gardening.

Find out how he can help you achieve your food production goals. Contact Brian