Conventional agriculture focuses on the macro-nutrients of Nitrogen (N), Phosphorus (P), and Potassium (K). Plants require a lot of N, P, and K. However, they cannot reach full potential without the major micro-nutrients.

There are many more mineral compounds that are required for plants to function other than N, P, and K. No matter how small the quantity required, these micro-nutrient elements are still crucial for optimal plant function. 

Secondary nutrients and micro-nutrients are very important in facilitating many critical plant functions and in enhancing sugar translocation, root strength and overall plant immunity.

The most critical of these micro-nutrients are Boron (B), Zinc (Zn), Manganese (Mn), Copper (Cu), Molybdenum (Mo), and Sulfur (S). Boron is critical for transporting carbohydrates through the plant system to help form and fill fruit.

Potassium Sulphate, Zinc Sulphate, Copper Sulphate, Manganese Sulphate, Magnesium Sulphate. These form part of a balanced amendment input and are allowable by certification standards. We use these in trace levels in our Complete Organic Fertiliser (C.O.F.) and tailor made amendments.

Available from most good garden centres Australia/N.Z wide.

Used in our Complete Organic Fertiliser, COF.

Boron is also a critical life sustaining element to microbial life in the soil.

Zinc and Manganese are both critical for proper reproduction and seed formation. Many trace minerals have proven to be critical in enabling plants to produce complete plant compounds, which allows them to be naturally resistant to pests and disease.

The benefits of supplementing secondary nutrients and micro-nutrients are far reaching. In fact, the presence of adequate secondary and micro-nutrients help other nutrients be more effective.

For instance, Boron is required to help a plant absorb Calcium. Many micro-nutrients act as enzyme co-factors and building blocks that enable plants to build complete proteins and compounds. They also aid in the development of larger, stronger roots and promote better plant immunity.

Micronutrients Available in Sizes
100g $5.00 AUD  
 Plus postage to anywhere in Australia

250g $9.00 AUD
500g $12.00 AUD


Zinc is a very important yield factor in that it is chiefly responsible for leaf sizing. With the leaf being the plant's primary solar panel, the overall size (surface area) of the leaf will directly govern the amount of sunlight that can be captured by the plant to feed photosynthesis. Photosynthesis is responsible for 90% of all plant production so improving photosynthesis is improving plant production. 

 In addition, when you supply adequate zinc levels to your crop, water absorption is enhanced as are flower and fruit development, as well.  Because water is required for all nutrient uptake and nutrient translocation within the plant, improving water absorption is key in achieving top production.

Zinc (Zn) is taken up by plants as the divalent Zn2+ cation. It was one of the first micronutrients recognized as essential for plants and the one most commonly limiting yields. Although Zn is required in small amounts, high yields are impossible without it.

Protein synthesis and growth regulation require Zn. Reduced hormone production due to a Zn-deficient plant will cause the shortening of internodes and stunted leaf growth.

Zinc is much less mobile within the plant, so deficiency symptoms first appear on the younger leaves.

Zinc aids synthesis of plant-growth substances and enzyme systems, and is essential for promoting certain metabolic reactions, which are particularly critical in the early growth stages.

As soil pH increases, zinc availability decreases.


Boron (B) is a micronutrient that is essential for cell wall formation and rapid growing points within the plant, such as reproductive structures. Interestingly, while higher plants require B, animals, fungi and microorganisms do not need this nutrient.

Boron (B) exists primarily in soil solutions as the BO3-3 anion – the form commonly taken up by plants. One of the most important micronutrients affecting membrane stability, B supports the structural and functional integrity of plant cell membranes. Boron-deficiency symptoms first appear at the growing points, and certain soil types are more prone to boron deficiencies.

Boron improves seed set under stressful conditions.

Although required in small amounts, boron is a component of all cell walls in the plant.

Boron deficiencies are more pronounced during drought periods, when root activity is restricted.

The line between deficiency and toxicity is narrower than other essential nutrients. Farmers should apply at proper rate and with proper placement.


Manganese (Mn) functions primarily as part of enzyme systems in plants. It activates several important metabolic reactions and plays a direct role in photosynthesis. Manganese accelerates germination and maturity while increasing the availability of phosphorus (P) and calcium (Ca).

Manganese plays a vital role in photosynthesis by aiding in chlorophyll synthesis.

Soybeans and wheat in particular require more Mn than many crops.

Manganese is very immobile in plants, so deficiency symptoms appear first on younger leaves, with yellowing between the veins. Sometimes a series of brownish-black specks appear.

Although Mn deficiencies are often associated with high soil pH, they may result from an imbalance with other nutrients such as calcium (Ca), magnesium (Mg), and Iron (Fe).


Copper (Cu) activates enzymes and catalyzes reactions in several plant-growth processes. Vitamin A production is closely linked to the presence of Cu as well, and it helps ensure successful protein synthesis. Classified as a micronutrient, only a small amount of this essential nutrient is needed for plant survival.

Copper is the most immobile of the micronutrients.

Many vegetable crops show Cu hunger, with leaves that lose turgor and develop a bluish-green shade before becoming chlorotic and curling.

Copper is necessary to chlorophyll formation in plants and catalyzes several other plant reactions.

Other metals in the soil, such as iron, manganese and aluminum, affect the availability of Cu for plant growth.


Molybdenum (Mo) is a trace element found in the soil, and is required for the synthesis and activity of the enzyme nitrate reductase. Molybdenum is vital for the process of symbiotic nitrogen (N) fixation by Rhizobia bacteria in legume root modules. Considering molybdenum’s importance in optimizing plant growth, it's fortunate that Mo deficiencies are relatively rare in most agricultural cropping areas.

Molybdenum-deficiency symptoms show up as a general yellowing and stunting of the plant. A Mo deficiency can also cause marginal scorching and cupping or rolling of leaves.

Several materials supply Mo and can be mixed with nitrogen (N), phosphorus (P) and potassium (K) fertilizers applied as foliar sprays or used as a seed treatment. Seed treatment is the most common way of correcting Mo deficiency because of the very small amounts of the nutrient required. A spray onto the garden area once every 3 years is sufficient.

Plants take up Mo as the MoO4-2 anion.

Molybdenum becomes more available as soil pH goes up, the opposite of most other micronutrients.

Relative Responsiveness of Selected Crops to Micronutrients
Crop B Cu Mn Zn
Alfalfa High Med Low Med
Apples High Med Low Med
Sugar Beet High Low Low Med
Citrus Med High Med Med
Corn Med Low Low High
Cotton High Low High Med
Grain Sorghum Low Med Med High
Lettuce Med High High Med
Oat Low Med High Med
Peanut High Low Med Low
Irish Potato Low Med Med High
Sweet Potato High Low High Med
Rye Low Low Low Med
Soybean Low Med High Med
Tomato High High Med Med
Wheat Low High High Low


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