Benefits of Foliar Fertilization

The following information is introductory material to Agmin Chelates liquid fertilizer and chemical products such as fungicides, algicides, and animal nutritional products. This is by no means the complete range of products, and new products are always being formulated, researched and developed at Agmin laboratories. For more information, please Contact Us.

What are the benefits of foliar fertilization nutrients?

Scientific research conducted in the 1950’s by Dr Tukey and associates at the Michigan State University lead to the validation of the theory that nutrients can be absorbed by foliar application to the leaf. It was shown that the foliar applied nutrients mainly enter through the stomata of the leaf (Figure 1.), and in some cases through the cuticles.

Although the quantity of nutrients absorbed by the leaf during foliar application may be small, it is compensated by a higher efficiency of uptake than applying the same quantity of nutrients to the soil. This is due to specific soil conditions where the nutrients can be lost by leaching, negated by chemical reactions, incorporated into microbial bodies and effected by many other fac- tors in the soil. These factors inhibit a portion, and in severely adverse soil conditions cause a majority of the nutrients to become unavailable to the plant roots.

There is a clear advantage of foliar application of nutrients in the case of adverse soil conditions, for the reason that one can overcome limitations of the soil and its ability to transfer nutrients into the plant. However, foliar application of nutrients is by no means a substitution for proper soil fertilizer management. It does however overcome those impediments which are adversely effecting the soil nutrition of plants.

A range of other benefits are associated with foliar fertilization. A few points are listed below:

  • Rapid results
  • Prolonged blooming
  • Improved plant health
  • Increased crop yields
  • Reduced growth stress
  • Growth during dry spells
  • Better cold and heat tolerance
  • Improved resistance to disease

What are the roles of the fertilizing nutrients?

Fertilization elements can be classified into three categories: macro nutrients - fertilizer elements (N, P, K, S), macro nutrients - Lime elements (Ca, Mg), and micro nutrients. The manipulation, interaction, and proportional fertilization of these elements is critical for the health of plants and crops. The complete role of each element in plant nutrition is too exhaustive to list here, however, some general points can be found below.

The macro nutrient fertilizer elements (Nitrogen, Phosphorous, Potassium, Sulphur) are required in large quantities by plants:

  • Nitrogen is essential for formation of amino acids, the building blocks of proteins. It increases the size and quality of fruits, and increases the vigour of the crop.
  • Phosphorous is involved in energy storage and transfer within the plant. It hastens maturity of the plant and is vital for seed, root and flower development.
  • Potassium is essential for protein synthesis and plays a role in the activation of enzymes. It improves the quality of seeds and fruits, and increases disease and cold resistances.
  • Sulphur is a integral part of amino acids for the establishment of proteins. It promotes growth and maturity.

The macro nutrient lime elements (Calcium, Magnesium) are also required in large quantities:

  • Calcium aids in cell division and formation. It is necessary for the development of firm fruit and increases the fruit set.
  • Magnesium is a key element in the production of chlorophyll (green pigment) that assists in photosynthesis (obtaining energy from light) of plants. It influences the early growth and aids in seed germination.

Why is the role of the micro nutrient so important?

Micro nutrients are in general used in lesser quantities than the macro nutrients, but are just as important for plant development and to establish a healthy and optimum crop. Many of the micro nutrients function as activators in the plant and as such are critical.

A brief summary of the micro nutrients can be found here:

  • Boron is essential for seed and cell wall formation. It also effects the nitrogen in the plant.
  • Copper is a major function in photosynthesis and assists in chlorophyll production. It also improves flavour of fruits and vegetables.
  • Iron acts as a oxygen carrier and works as an activator for enzymes that control respiration.
  • Manganese aids in the utilization of nitrogen within the plant, and is essential in Phosphorous and Magnesium uptake.
  • Molybdenum is required in small quantities which helps reduce the nitrates to ammonium in plants. A deficiency in Nitrogen can be directly related to a deficiency in Molybdenum.
  • Zinc has many functions and is needed for synthesis of growth hormones and protein. It helps increase the leaf size, fruit size and its qualities.

Next we will discuss in detail why it is essential to perform soil and plant tissue test. Soil and plant tissue testing enables early detection of the so called "hidden hunger" of plants for macro and micro nutrients. It is a proactive way to optimise your crop production, and to minimize applying fertilizer elements which might seem to be lacking but can be caused by factors such as an imbalance in micro nutrients.

An example of this is a deficiency in Molybdenum, which can cause the nitrates to accumulate in the leaves and the plant cannot use the nitrate in the production of proteins.

How do we know what our soil and plants require?

Soil and plant tissue testing is essential to reach an optimum and healthy crop production. Liebig’s Law of the Minimum states that the growth of the crop is controlled by the scarcest resource. This means that the fertilization element that is scarcest in the soil or plant will be the limiting factor for the development of an optimum crop.

It is therefore recommended by Agmin that at least one soil test is performed prior to planting/seeding, and up to three plant tissue tests during the season to review what the crop requirements are during the growth stages for optimum crop production.

Agmin works in conjunction with laboratories that are accredited by the Australian Soil and Plant Analysis Council (ASPAC) in order to ensure that quality of analysis results are fully validated. After the analysis of the soil or plant tissue the results are used in a nutritional evaluation by Agmin’s agronomist to make a recommendation of what actions are available to you for the improvement of your crop. This is important both prior to planting/seeding and during the growth stages of the crop. A single soil or plant tissue test with recommendations is a very inexpensive way to establish any deficiencies or problems in both the soil and the plant. Agmin provides complete cost effective soil tests and plant tissue analyses for all important fertilization elements including test such as Electrical Conductivity, pH, Phosphorous Buffer Index and more.

The recommendation from Agmin also contains evaluation of fertilization elements interaction and antagonism. There is a complex interplay between elements, and how they affect each other in the soil plant. Some elements can enhance or suppress each other. An example of this can be seen in figure 2 of the complex interaction and antagonism of elements that has to be taken into consideration during an evaluation.

Why do Agmin products perform so well?

Agmin was the first lignosulphonate chelator of micro nutrients in Australia. On this page the terminology and unique features of Agmin’s product range will be discussed, and why the products perform so well, and why they are very cost effective and environmentally friendly.

Lignosulphonate is derived from Lignin and is a by-product of the pulp from the paper industry, meaning they are organic in nature and environmentally friendly. Lignosulphonate is processed prior to usage in Agmin products to break down the lignosulphonate (usual misquoted in the industry by referring to it as low molecular weight lignin, albeit the technical discussion is beyond the scope of this article.)

The lignosulphonate in Agmin’s liquid fertilizer range (see next page for product range) has a unique property where it uniformly "chelates" many of the nutrients. Chelating derived from the Greek word "chele" means "claw". This claw or chelate holds on to many nutrients. (Please see the figure at the bottom of the page for a visual representation of the chelation of Zinc.)

The lignosulphonated chelation in general terms prevents the nutrients to be immobilized in soil application. In foliar application the lignosulphonate binds the protected nutrients to the leaf, assisting in rain fastness, and the surfactants and penetrants increase the efficacy of absorption.

Benefits as a foliar application:

  • Is naturally tacky and exhibits excellent binding properties on leaves, assisting in rain fastness.
  • Ability to act as a wetting and dispersing agent.
  • Easily absorbed by plants.
  • Translocate readily within the plants.
  • Easily decomposed with the plant so that the trace element becomes available.

Benefits as a soil application:

  • Having a stability not easily replaced by other nutrient elements in the soil.
  • Each of the elements chelated are very stable against hydrolysis.
  • Trace elements chelated are resistant to microbiological decomposition.
  • Not easily precipitated by ions or colloids in soils.
  • Metal chelates are available to plants either at root surfaces or within the plant.
  • Chelated micro nutrients are not detrimental to plants at concentrations required to prevent deficiencies.

An overview of Agmin foliar fertilization products

The Agmin product range covers all nutrient deficiencies and maintenance applications. Not only is Agmin’s product range very price competitive, but the efficacy compared to traditional liquid fertilizer is greatly enhanced by Agmin’s chelation technologies, and included binders, penetrants and surfactants.

Agmin also offers Prescription Mixes, based n soil or/and plant tissue analysis when ordering 200L or more. This enables Agmin to produce a tailored mix to your crops needs for a single application which also reduces cost.

Products range from:

  • Single deficiencies, Zinc, Iron, Calcium, Potassium, Boron, Copper, Iron.
  • Nutrient mixes with a complete spectrum of macro and micro nutrients (e.g. Vigor-Lig Plus) to raise the complete balance of your crops nutrients for optimal production.
  • NPK fertilizers (e.g. UAN Trace Chelate [39% N] with trace element benefits and also Humic and Fulvic Acid based fertilizers.
  • Crop sprays for larger application in broad acre settings.

Summary of Agmin product Benefits:

  • Exceedingly cost effective and competitive products.
  • More efficient than traditional liquid fertilizers.
  • Quality controlled by Agmins laboratory facilities.
  • Prevents lock up of nutrients in the soil when performing soil applications.
  • Binds to the leaves of the crop with foliar applications for greater nutrient uptake.

Foliar Liquid Fertilizers

AGB Zinc Chelate
AGB Zinc & Manganese Chelate
AGB Calcium & Boron Complex
AGB Potassium & Boron Complex
AGB Trace Chelate
AGB Boron Complex
AGB Vigor-Lig Plus
AGB Iron Chelate
AGB Manganese Chelate
AGB Copper Chelate
AGB Magnesium Chelate + TE
AGB Zinc & Copper Chelate
AGB Zinc & Iron Chelate
AGB Zinc + Mn + Cu Chelate
AGB Zinc + Mn + Fe Chelate
AGB Zinc + Cu + Co Chelate
AGB Humic NPK 0:8:21 + TE
AGB UAN + Trace Chelate
AGB Humic Polyphos & Nitrogen + TE
AGB Vig-Grain Plus
AGB Prescription Mix
AGB Nutrimin Crop Spray
AGB Trace Element Additive for UAN

Beyond fertilization products: Algicides, Fungicides, & Animal Nutrition

Agmin offers a range of ag-chemicals. These range from the very popular algicide "Cupricide", a copper complex based algicide that is extremely environmentally friendly, safe, and APVMA registered.

Agmin supplies an APVMA registered Systemic Fungicide named HortiPhos 600 based on 600 g/L Phosphorous Acid to fight phytophthora disease (dieback) and downy mildew, a well known product in the market and cost effective.

Agmin supplies a variety of livestock nutritional products, such as the well known Nutrimin range of Drenches (and Drench Plus with vitamins A,D,E). These are supplied in liquid form for application in troughs or directly as a drench to the livestock.

In addition to this a product, Nutrimin Pasture Spray, enhances the nutrient quality of the pasture on which the animals graze. Agmin supplies a pH buffering product that is APVMA registered, called AgBuffer 550 based on 350 g/L Glycolic Acid to reduce pH and 200g/L non-ionic surfactant to decrease the surface tension of the spray-droplets.

Nutrimin Product Range

AGB Nutrimin Pasture Spray
AGB Nutrimin Drench
AGB Nutrimin Drench Plus


AGB HortiPhos 600

pH - Buffer

AGB Ag-Buffer 550


AGB Cupricide Algicide
AGB Kupramine

Visit our Cupricide Algicide Specific Website:

For further information on all of our products, please
Contact Us or call our toll free number 1800 154 433.