Foliar feeding is an economical and efficient method of fertilisation. It should not be used to replace a good soil fertility program, but it can be a remarkable yield-booster in conjunction with a well-balanced soil, and it can be an incomparable problem-solver in many situations. It has been proven that foliar methods of application can have between 8 – 20 times more effective for uptake of applied nutrients compared to traditional uptake through root mechanisms. It is also suggested that only 10 – 30% of traditional N-P-K fertilisers are taken up by the plant, with approximately 80% of foliar fertiliser taken up comparatively.

Foliar application allows for less fertiliser with better results

Foliar fertilisers can bypass problems associated with root absorption, like nutrient competition, nutrient lock-ups, leaching and soil structure problems. This fertilisation method offers rapid rescue response in times of stress – frost, drought, storm damage, pest and disease pressure – and it offers that extra energy boost during periods of nutrient demand. Foliar feeding can also be used to manipulate growth energies, i.e. to switch a plant from a growth response to a fruiting response.


Foliar fertilising is most efficiently achieved with mist-type sprayers. The smaller the particle size, the better the response and the less fertiliser is required to achieve the same end result. The leaf hairs surrounding the stomata attract nutrients within fine water droplets more effectively. There is little point in applying liquid fertilisers through overhead irrigation if you are seeking a foliar response. There may still be some soil benefits associated with this approach, but the potency of the foliar response will not be achieved. Boom sprays can be used, but nozzles that mist or fog should be fitted. Nozzles that produce a cone-shaped pattern and spin the spray upon leaving the nozzle are particularly effective.

Timing is critical with application of foliar sprays, as young foliage appears to absorb nutrients more efficiently. In small crops and broadacre systems, foliar fertilising is particularly effective with young plants in the third to sixth leaf stage. A second spray around 40 days after emergence can be used specifically to change the plant from growth to fruiting.

It is always best to foliar spray in the early morning or evening, when relative humidity is high, rather than in the heat of the day. There are two main reasons for this fact: if a fine mist is applied, there is a risk that the hot sun will evaporate the solution before it can be absorbed by plants. Secondly, when temperatures exceed 32c, plants transpire and release rather than absorb moisture. Similarly, when temperatures fall below 10c, metabolic rate and nutrient translocation slows down considerably, and foliar sprays are less effective. It should always be remembered that the majority of the stomata are on the underside of the leaf, and consequently this should be the target for spray solution.
























NutriMAX PhosCal6.00%11.80%3%0.50%0.01%0.02%-1.50%0.30%---
NutriMAX Triple Feed NPK13%10%13%0.10%-------0.50%
NutriMAX Cal-N Fulvate7.45%-1.50%--0.20%-0.02%-0.01%15ppm5%
HumiPLEX Trace---4.30%4%3.10%0.69%0.38%0.27%0.03%105ppm-
HumiPLEX Mang Zinc Copper---9.20%6%8%2%----1.60%
BioMAX F75-----------75%
BioMAX BOOST0.90%0.40%3.25%2.20%30ppm0.00%2ppm7ppm50ppm0.5ppm0.5ppm3.20%
BioMAX Piranha 18% Kelp0.10%0.01%4.50%2.50%--------
BioMAX Vermi Liquid850ppm1000ppm900ppm0.10%1mg/kg-1.00%0.05%50mg/kg---

LawrieCo’s foliar biostimulants product range optimise plant carbon exudates, enhancing soil carbon building

Popular products in our range of foliar nutrition include:

NutriMAX PhosCal Micronised Calcium 26%  Phosphorus 12% Nitrogen 6%  Silica 7%  Boron 1.5% Complexed with Fulvic 2% & Biostimulants

BioMAX Boost Kelp Fish Hydrolysate, Fulvic and natural growth hormones.

Nutrimax Growth Nitrogen 10%, Phosphorous 7.6%, Potassium 4.5% + Calcium 3% complexed with Biostimulants

 BioMAX F75  Super concentrated liquid Fulvic 75%, Powerful chelation and biology stimulant, ensures nutrient efficacy and plant uptake.

HumiPLEX Trace, Zinc 4%, Manganese 3%, Copper 0.7%, Boron 0.4%, Iron 0.3% with Cobalt and Molybdenum, plus powerful Fulvic chelation. Mineral Sulphates for rapid plant absorption


PHOSCAL Plant Applied Nutrition Delivering

Consistent Crop Yield Increases in Trials.

(08) 8260 1134    |

PHOSCAL – Activating plant photosynthesis for enhanced root Carbon Exudates. 

Yield performer and quality booster across all crop types. Formulated with ideal bio
nutrient sequence for plant uptake of nutrients. Silica aids plants natural response to pest and disease pressure. Silica and boron synergise with calcium and improve its uptake by plants, the start of bio nutrient sequencing.

Key component of LawrieCo Soil Carbon Regeneration Program, for all plants.

Phoscal is one of the key products in LawrieCo’s Soil Carbon Regeneration System, ‘The 6 Steps’, incorporating biological inoculants & stimulants. It’s all part of the science that makes building soil carbon possible. Our 25 years of Research and Product Development has culminated in a suite of products that support soil carbon regeneration whilst maintaining / boosting the productivity of your enterprise.


• Average increased return of $300 per hectare

• Significant increase in yield

• Improved plant health and crop yields


• Increase in Fruit Size and Weight

• Greater % of Fruit in higher Export Grade

• Increase Crop Value $4,816 per hectare

• Return $49 Per Nutrient Dollar Invested


• Early flowering response & improved retention in legume & bean crops.

• Average increase: 510 kg/Ha

• Income increase: $ 295.8/Ha



• Phoscal has contributed to an almond yield increases

• Trees in areas treated with Phoscal are exceptionally good, up to 50% bigger than we would expect them to be

PhosCAL requires robust agitation, as a mineral suspension, to avoid blockages – LawrieCo recommends agitating with an Agi-Mate portable agitator for best performance.

The Secrets of foliar fertilisation

Foliar application is 8 to 10 times more effective than other fertiliser application methods

The value of foliar feeding was proven by research at Michigan State University many years ago.  A project partially funded by the atomic Energy Commission used radioactive tagged nutrients to prove that a plant can feed through the leaves.  In fact, they proved that it is eight to ten times more effective to feed a plant that way in terms of the amount of nutrients necessary to do the same job. 


Foliar feeding is useful and effective in correcting plant deficiencies and we use it primarily to increase yield and quality through precision nutrition. If leaf analysis or field monitoring confirms any shortage, the problem can be rapidly and efficiently corrected with the appropriate foliar fertiliser. If foliar feeding is done correctly, you should see visual results in approximately 48 hours using most products. Please remember that mineral suspension products have a slow release-pattern of up to 2 weeks. There are, however, several factors that determine the success of the foliar approach. The secrets of foliar fertilising are as follows:

  • 60% calcium base saturation is required to ensure maximum foliar uptake. This is determined by a soil test based on the Albrecht method such as the one we use by the Australian Perry Agricultural Laboratory here in Adelaide.


  • A fine mist spray, preferably with air assist, is required to supply the small droplet size, which is necessary to gain entrance through the stomata – the tiny breathing pores largely located on the underside of the leaf. These pores are each surrounded by a picket fence of fine hairs, which prevent the entry of larger droplets. It is better to spray small amounts of material more frequently than it is to drench large amounts of material.


  • Always mix sprays as thoroughly as possible. The ultimate sprayer is a mist sprayer that homogenises the solution and applies it in a fine mist across a large swath.


  • Good timing guarantees peak performance. The best time to foliar feed is between 7 and 10 am or after 5pm when the plant’s stomata (the small opening on the underside of the leaves) are open. However, if the temperature is 25°C or above at 7am don’t bother to spray, as it will have little effect – the stomata will be closed to help the plant hold water. The best temperature is around 21ºC.  If the weather is very hot and dry, then you may have to spray between 2 and 4 am. Always be careful of burning the leaf when bright sun is allowed to shine on the spray.


  • Foliar-fertilising can be invaluable during winter, as root uptake of nutrients like phosphate is negatively affected by cold or wet conditions.


  • Young foliage is particularly absorbent. Flowering and subsequent seed or fruit formation is highly nutrient-dependent. Leaf analyses and foliar correction should be tied to these two critical periods – i.e. foliar spray field crops 30 days after germination and again before flowering. Foliar-fertilise fruit crops before flowering and whenever a new flush promises good absorbency. Foliar fertilisers can also be used to build fruit size (if necessary).


  • Use foliar-enhancers with all nutrient applications. The four categories of foliar enhancers include chelating agents, uptake enhancers, natural hormonal stimulants and full-spectrum feeders. There are only two materials that encompass all four categories, and these are fulvic acid (BioMax F75 Fulvic ) and kelp (BioMAX Piranha or BioMAX Kelp). Alternatively use BioMAX Boost that is formulated with Kelp, Fish, Fulvic and Triacontanol.  Both fulvic and kelp can chelate nutrients, increase their uptake, supply growth and flowering hormones and provide complete trace mineral coverage (i.e. kelp contains over 60 micronutrients).
  •  Monitor conductivity and pH of the spray solution. Conductivity should be as close to 2 mS/cm as possible. If the conductivity of the final dilution is less than 1.2 mS/cm there will be a disappointing response. If it is higher than 2 mS/cm there may be a problem with leaf burn. The ideal pH range of the solution should be between 6.2 and 7 pH where possible, with a more acidic solution (sour) producing a reproductive response (fruit, grain, ears etc), and an alkaline solution (sweet) stimulating growth.


  • Don’t use the foliar approach to replace soil-based nutrition! Maximum results will always be achieved with a holistic approach, where everything is considered and managed efficiently. The goal is to realise the original, natural genetic potential of your particular crop.

  • It is always advantageous to agitate / mix well foliar nutrition and AG chemicals prior to transferring them to the spray cart. This ensures all active ingredients are accurately dispersed prior to decanting from their containers. Always fill the spray tank with water prior to adding ag-chem and nutrition with agitation on. Mineral suspension (for example PhosCal) products require particular focus in this area, they require a thorough mixing before transferring to the spray cart, once they have been decanted from their original containers the “suspension agents” are no longer sufficient to keep the product dispersed, so constant agitation in the spray tank is a MUST.  LawrieCo offer a range of custom made agitators that make this step easier as we know time gets in the way, but it’s 100% worth getting this step right. 

This chart is similar to Mulder’s Chart which demonstrates the phenomenon of antagonism and stimulation of nutrients in the soil and their affect on plant uptake, but this chart demonstrates the phenomenon of nutrient uptake inhibition (only) at work within the leaf instead.


Mulder’s Chart together with this chart can be particularly valuable in explaining leaf analysis data in conjunction with soil analysis data and in deciding upon appropriate fertiliser programs.


BOOST combines Kelp, Fish and Fulvic including natural growth hormones.

It is designed for foliar and fertigation application in all broadacre crops, dairy, pasture, horticulture and viticulture.

The product contains a natural balance of minerals, vitamins, oils, proteins, amino acids and trace elements.

BioMAX F75

Maximise liquid fertiliser nutrient efficiency.


Fulvic’s unique ability to form multiple strong bonds with minerals ensures nutrient efficacy and plant uptake.


Buffer against high salts and other toxicities in water and soil.

BioMAX Piranha

Enhance plant health and fruit quality with potent chelating agents, natural plant hormones and complex sugars


Increase resistance to frost and environmental stresses


Boost yield and quality by improving flowering and fruit set

Call your LawrieCo Area Manager to discuss recommendations that suit your crop requirements.

Offers & Information

LawrieCo 6 Steps

LawrieCo’s Soil Carbon Regeneration System Incorporates biological applied science and regenerative bio fertilisers. It’s the science that makes building soil carbon possible.

LawrieCo’s passion for rebuilding soil carbon dates back to prior to the formation of LawrieCo as a company. Back to the days when the ‘R&D’ to farm sustainably and to build fertility happened on Adrian Lawrie’s broadacre cropping property on the edge of the Flinders Ranges. At this early stage the key drivers for rebuilding soil carbon were its value in building fertility, water-use efficiency and it’s link to improved farm gross margins.

Our 22+ years of Research and Product Development has culminated in a suite of products that support soil carbon regeneration whilst maintaining / boosting the productivity of your enterprise.

Our carbon crediting program is world class connecting growers with rigorous the Federal Government Emission Reduction Fund, ensuring the viability of credits issued.

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47 Naweena Road,Regency Park SA 5010
Telephone 08 8260 1134