Fundamental Frequently Asked Questions

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Frequently Asked Questions


pH is defined as the degree of acidity/alkalinity of a solution. It is identified on the pH scale ranging from 0 to 14, with a pH of 7 representing the neutral point. Solutions with a pH less than 7 are considered acidic, while those above 7 are considered basic (alkaline). The pH scale is logarithmic, meaning small changes in pH represent large changes in the degree of acidity or alkalinity. For example, a solution with a pH of 5 is ten times as acidic as a solution with a pH of 6, but a solution with a pH of 5 is 100 times as acidic as a solution with a pH of 7. For plants this is relevant, as the majority of plants will undergo maximum unassisted uptake of nutrient in a pH range of 5.8 to 6.3.


Foliar feeding is the technique of applying liquid fertilizer directly to the plants leaves. Clinical research has shown that plants absorb nutrients from foliar feeding at the rate of approximately 30cm per hour to all parts of the plant. Foliar feeding is considered especially useful for introducing trace elements, or for the emergency feeding of plants which are found to have a specific shortage of a particular element. In some cases, as with the example tomatoes, it's actually believed that foliar feeding during flower set causes a dramatic increase in fruit production.

It must be considered that foliar feeding alone will not satisfy your plants nutrient requirements. This is because foliar absorption is limited by the relative barrier of the cuticle.


It is possible to use any full spectrum nutrient to foliar feed your plants, but it is advised that the nutrient be organic or organic based. To avoid nutrient burn the foliar nutrient solution strength should be no more than 1/3 of the manufacturers recommended dosage for root zone feed programs. The ideal temperature to foliar feed at is approximately 22ºC (71.6 degrees). This is the temperature when stomata on the underside of the leaves are open, at temperatures above 28ºC (82.4) the stomata may not be open at all. This would deem the foliar feed ineffective. Keeping this in mind, it is important to foliar feed during the cooler parts of the day. For optimum results and to prevent burning it is best to foliar feed early in the morning or late in the afternoon.

It is important to foliar feed with a high quality sprayer, the sprayer must be able to atomise the solution into a very fine mist. Also ensure that the pH of your solution is adjusted to between 6.2 and 7 (debatable). During the feeding process, it is important to spray both the top and underside of the leaf surface until the liquid begins to drip off the leaves. At a minimum foliar feed once a week and if there is any white residue found on the leaves rinse the foliage with pH adjusted water to reduce salt build-up.


Root Rot is a condition generally suffered by plants root systems due to poor soil drainage or over watering. The excess water makes it difficult for the roots to get the air that they require, making them rot. Root rot is best prevented or controlled as there is no cure.

The most common form of root rot is due to Pythium spp. When severe the lower portion of the stem becomes slimy and black. Usually, the soft to slimy rotted outer portion of the root can be easily separated from the inner core.


There are sixteen essential nutrients which plants require. Three are directly absorbed from the atmosphere (Oxygen, Carbon and Hydrogen). While the other thirteen essential elements must be absorbed through your plants growing medium. The list of thirteen elements is further broken down into three key groups. They are defined as macro, secondary and micro nutrients.

Macro nutrients include Nitrogen (N), Phosphorus (P) and Potassium (K). These are the key elements required for plants throughout their life cycle. Nitrogen is an essential component of amino acids and, therefore, of proteins which include nucleic acids, enzymes, and the green, light-harvesting pigment, chlorophyll. It is also the nutrient which normally produces the greatest yield response in crop plants.

Phosphorus is an essential part of the enzymes which help the crop to fix light energy. It forms an integral part of nucleic acids, the carriers of genetic information, and is important in stimulating root growth.

Potassium is involved in processes which ensure carbon assimilation and the transportation of photosynthates throughout the plant for growth and the storage of sugars and proteins. The potassium ion is also important for water regulation and uptake.

The secondary elements are equally as important but are required in smaller quantities. These include Magnesium (Mg), Sulphur (S) and Calcium (Ca). Magnesium occurs in chlorophyll and is also an activator of enzymes, while sulphur forms part of two essential amino acids which are among the many building blocks of protein. It is also found in vitamin B1 and in several important enzymes. Calcium is required for plant growth, cell division and enlargement. The growth of root and shoot tips and storage organs is also affected by calcium as it is a component of cell membranes. Calcium is also vital for pollen growth and to prevent leaf fall.

Finally, there are micro nutrients these are equally as important but are only required in minute quantities. These are Iron (Fe), Manganese (Mn), Zinc (Zn), Boron (B), Copper (Cu), Molybdenum (Mo) and Chlorine (Cl).


Photosynthesis is the process of converting light energy to chemical energy and storing it in the bonds of sugar. This process mostly occurs in plants and some algae. The conversion of unusable sunlight energy into usable chemical energy, is associated with the actions of the green pigment chlorophyll. For the conversion to occur plants require light energy, CO2, and H2O.

Photosynthesis takes place primarily in plant leaves, and little to none occurs in stems, etc. The stomata are holes which occur primarily in the lower epidermis and are for air exchange: they let CO2 in and O2 out.


The general rule is that leaves are sugar production factories for plants and that the sugar is critical for the flowering process. So, always refrain from removing leaves from your plant.


There are a number of different devices available to measure the strength of nutrient solutions. Each of the methods relates back to the Electrical Conductivity (EC) of the solution. The Electrical Conductivity is a measure of a material's ability to conduct an electrical current.

When an electrical potential difference is placed across a conductor, its movable charges flow, giving rise to an electric current. The conductivity is defined as the ratio of the current density to the electric field strength.

Other common measurements used to define nutrient strength are the Conductivity Factor (CF), Total Diluted Solids (TDS), and Parts Per Million (PPM).
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