The Webster Dictionary defines the word scientific as “the use of knowledge pertaining to science, especially to natural science.” In this context, modern, chemical farming is anything but scientific. In fact, in many ways it is anti-science, constantly denying irrefutable natural laws in the pursuit of dubious chemical solutions. It is not scientific to don your sweat-soaked space suit to poison your entire working environment, indiscriminately slaughtering beneficial insects above ground and your precious microbial workforce and defense team beneath the surface. It is anti-science to constantly expose the human body to these toxins, and it defies both natural and moral laws to supply chemically contaminated produce to the community at large.
The original introduction of chemical fertilisers was not some sort of scientific breakthrough. Industry needed a market for the nitrogen-based products of their armaments factories following World War I, and agriculture was targeted.
When these high-leaching fertilisers had demineralised our soils, strip-mining our carbon reserves in the process, then science was enlisted to help clean up. The American consultants refer to the ensuing flood of pesticides, fungicides and herbicides as ‘toxic rescue chemicals’, and this is exactly what they were. Poor fertility and nutrition had weakened the immune systems of plants and the natural, microbe-based defense mechanisms in the soil had been compromised.
Nitrate-packed, low-brix plants emit an infra-red radiation, which attracts nature’s garbage composers – the insects. The truly scientific approach should have been: "How do we work with natural laws to address the root-cause of these problems?" – i.e., soil and plant nutrition. Instead, the rescue mission promoted a war – a ludicrous war against nature, with the chemical assault teams now an integral part of the farming landscape.
NTS' Nutrition Farming® approach utilises real science. In this pragmatic approach, every input is evaluated in terms of its biological impact. This is not an organic approach, as there are many valuable inorganic inputs that do not compromise biology. Anything that works without causing damage is considered valid. Nutrition Farming® is about farming the biological workforce and utilising nutrition and scientific principles to produce better yields, better quality and more minerally-enriched food to sustain society.
Measurement is the keystone of the scientific approach and, in this context, soil testing is an indispensible guideline for fertility management. NTS' Soil Therapy™ – our free, in-depth fertility analysis – offers precision nutrition based on soil science and the critical importance of nutrient balance in the high-production fertility equation. A perfectly balanced soil offers maximum nutrition for microbes, plants, animals and humans, but often this is not easily achieved.
While working toward equilibrium, we need other forms of measurement to manage fertility. NTS' Plant Therapy™ Sap Analysis System monitors plant health and provides an insight into plant food requirements during the crop cycle. Nutrient uptake problems are generally related to ‘lock-ups’ in a poorly-balanced soil. Foliar nutrition is often the best option to bypass these soil-based problems.
The NTS Plant Therapy™ Sap Analysis System involves seven tools used to facilitate nutritional diagnosis and analysis. These include the NTS Sap Extractor, the Refractometer, the Plant Sap pH Meter, the Plant Sap Conductivity Meter, the Plant Sap & Soil Nitrate Meter, the Plant Sap Potassium Meter and the Plant Sap Sodium Meter.
The NTS Sap Extractor
All of the above diagnostic tools require 2 – 3 drops of plant sap, usually extracted from the leaf or stem. Garlic crushers are the most commonly used extraction tool, but here there are strength of construction and design problems that can drive a man to drink. It is not uncommon to shatter a conventional garlic crusher on every second outing. Several growers and consultants have modified vice grips by welding on steel plates. Perfectionists, like Bob Pike from Pike Agri-Lab Supplies in the US, have developed the mother of all extractors, utilising a hydraulic press powered by a 4-tonne bottle jack.
However, speed and ease of extraction, combined with pocket-sized portability are the essential design features for a sap extractor. In this context, NTS still favour the garlic crusher design, but with modifications and strength enhancening features. The NTS Sap Extractor is virtually unbreakable. It has a unique pressure point design, which facilitates rapid sap extraction. It includes a head cleaning tool for the removal of fibrous plant material, and it has been treated to avoid discolouration in dishwashers.
The Refractometer is a 15 cm-long, tube-shaped instrument, much like a shortened telescope. It has an adjustable eyepiece at one end and a prism with a fold down plastic cover at the opposite end. 2 – 3 drops of plant sap is deposited on this prism. The light passing through the plant sap is refracted (bent) in relation to the amount of dissolved solids in the liquid. These solids reflect plant sugar levels, but are also an indication of mineral content and general plant health. The Refractometer measures brix levels.
High-brix crops will have a higher sugar and mineral content, higher true protein content and a greater specific gravity or density. High-brix produce is sweeter tasting and more minerally nutritious, with a lower nitrate and water content and better storage characteristics. Elevated brix levels also confer an inherent insect resistance, as the plant tends to produce more alcohol from fermented sugars. This alcohol content is inconsistent with the digestive systems of many leaf and fruit-eating insects. In fact, it is toxic to these pests, resulting in a reduction in pesticide usage.
Crops with a higher sugar content will also have a lower freezing point, with an associated protection against frost damage. Brix levels are also an indication of soil fertility. Low-brix plants are inevitably a reflection of poor mineralisation. Biologically available calcium and phosphate will be deficient in the soil, and deficits of these two elements will also increase weed pressure. Broadleaf weeds and sourgrasses grow more prolifically in soils lacking calcium and phosphate. In fact, it is possible to kill a dandelion with the simple application of soft rock phosphate, which contains both of these minerals.
Analysing brix readings:
The Refractometer is an invaluable fertility monitor. Brix readings can define the probability of yield limitations and the likelihood of pest and weed pressure. This instrument can also highlight destructive fertilising and crop management practices. For example, brix readings will often drop following the misuse of dolomite, an oversupply of nitrogen and potassium (particularly muriate of potash) or following blanket-herbiciding.
Brix readings can also be a guideline for calcium requirements – i.e., a clear distinct line separating the blue and white fields when viewing through the eyepiece, indicates acidic, calcium-deficient soil conditions, while a fuzzy line indicates more alkaline conditions with better calcium levels.
US consultant, Dr Carey Reams, developed a crop-specific comparison chart for brix readings, called ‘The Refractive Index of Crop Juices’ (available free of charge from NTS). In general, brix readings will vary from 4 (poor) to 12+ (excellent), with fruit crops usually reading higher than vegetable crops. Potatoes are a stand-out exception, where 7 is considered an excellent brix reading. Consistent brix readings of 12 or higher are the ultimate goal. This can be achieved with a good soil-balancing and remineralising program (i.e., Soil Therapy™), combined with bio-available fertiliser inputs. Levels can then be fine-tuned and maintained with a foliar program (Plant Therapy™). Soft rock phosphate (NTS Soft Rock™) is the one soil fertiliser most likely to effect brix levels favourably.
Factors influencing brix levels:
There are several environmental and nutritional factors that can affect brix readings, and these must be factored in when analysing brix results.
- Storms or impending weather changes will lower readings, i.e., the plant translocates sugars to the roots when anticipating periods of stress.
- Droughts can raise the reading, since the water content is low and the plant juices are more concentrated.
- Several consecutive cloudy days will cause brix levels to drop, i.e., sunlight is required for photosynthesis and plant sugar production.
- The lower the humus content of the soil, the faster the brix readings will drop following a prolonged cloudy or rainy period.
- Brix levels should remain uniform throughout the plant. If there is a marked variation from the top to the bottom of the plant, then soil imbalance is the most likely cause. The phosphate/potassium ratio is the chief suspect here.
- There should always be a variation in brix levels at different times of the day. Plants translocate sugars to the roots at night, and early morning readings should always be lower than afternoon readings, when the sugars are back in the leaves. If there is no variation in brix levels during the day, then a blockage is the likely cause, whereby the sugars are trapped in the leaves. In this instance magnesium sulfate (epsom salts) can be used to flush the plant and restore health.
The Plant Sap pH-Meter
American researcher, Bruce Tainio, has discovered that plant sap pH is a simple and accurate guideline for the following:
- Enzymatic breakdown of carbohydrates (sugars) for plant growth and vitality.
- Risk potential for insect damage.
- Risk potential for foliar disease attack (fungi, bacteria and viruses).
- Nutritional balance in the growing crop.
- Quality of fruit and vegetables.
- Shelf-life of fruit and vegetables.
The desired sap pH-level for optimal plant growth and production is pH 6.4. Conventional pocket pH meters can’t be used to measure sap pH, as their electrodes must be immersed in fluid, and this is not practical in measuring small quantities of plant sap. The only instrument capable of measuring sap pH with ease is the Plant Sap pH Meter. This precise, high-quality instrument has a small sink-like receptacle, which can accurately measure pH with just a few drops of fluid. If sap pH exceeds 6.4, then the most likely cause will be a shortage of the anions nitrogen, phosphate or sulfur. At pH 8 the likelihood of insect attack is 100%.
Conversely, if sap pH is lower than 6.4, then there is a cation problem, with possible deficiencies of calcium, magnesium, potassium and/or sodium. Low sap pH suggests a far greater potential for foliar disease. For example, at pH 4.5 the probability for fungal attack is 100%.
Other forms of pH monitoring:
The Plant Sap pH Meter can also be used to monitor soil pH. Plant nutrient availability is pH-dependent. 6.3 is regarded as the ideal soil pH for maximum nutrient exchange. When soil pH falls below 5.8, there are a number of nitrogen-fixing organisms that won’t survive, and, when soil pH increases beyond 8, there are similar problems with beneficial fungi. The acid/alkaline dichotomy also relates to vegetative vs reproductive energies in production – i.e., acid soils produce poor vegetative growth, while crops grown in very alkaline soils may have problems with flowering.
The Plant Sap pH Meter can also be used to monitor the pH of foliar spray solutions. In general, a pH of between 6 and 7 is desirable for all crops, but early growth can be pushed with more alkaline sprays (i.e., pH 7 to 7.4), while fruit, root or seed-producing foliars require a spray solution pH of 6.4.
The Plant Sap Conductivity Meter
This tool is also manufactured by the hi-tech Japanese Company, Horiba, and marketed by NTS in Australia. The Plant Sap Conductivity Meter can measure the conductivity of plant sap with just two drops of juice.
Plant sap conductivity measurements indicate the level of simple ion uptake. In a low-brix crop, if the sap electrical conductivity (EC) is too low, this is an indication that elements are not being made available to the plant. Usually this will relate to low electrical conductivity in the soil. Soil conductivity is seen in this system as a measure of the energy released from fertilisers for plant growth. Ideally, a crop should be started with soil EC readings of around 200 µS/cm, and soil conductivity should be gradually increased to around 600 µS/cm when the crop is fruiting or seeding. When soil conductivity exceeds 1200 µS/cm, most plants won’t survive.
The Plant Sap Conductivity Meter can be used to measure both plant and soil EC. If the sap EC is too high, elements or ions are not being ‘complexed’ correctly, and ions such as nitrate nitrogen may be at excessive levels.
Other forms of conductivity monitoring:
The Plant Sap Conductivity Meter can also be used to monitor the conductivity of foliar spray solutions. An EC reading of 2000 µS/cm is ideal for both foliar spray solutions and nutrients to be fertigated. If the reading is 1200 µS/cm, then fertiliser performance will be disappointing, and if EC exceeds 2000 µS/cm, then crop burn is likely.
The Plant Sap & Soil Nitrate Meter
When the soil has been completely balanced and biologically activated, then the two elements with the most potential to limit yield in high-production horticulture will always be nitrogen and potassium. Ensuring that you always have the right amount of nitrogen at the right time is the keystone of high production. Nitrogen excesses or deficits will limit yield, and, due to the volatility and instability of this principle energy source, exact requirements can sometimes be difficult to assess.
NTS market the Plant Sap & Soil Nitrate Meter, manufactured by Horiba, which accurately measures the amount of nitrate nitrogen in the plant sap at any given time. This in-field diagnostic tool offers precision and reliability within 5% accuracy of conventional leaf analysis data. The Plant Sap & Soil Nitrate Meter allows fingertip nitrogen management and enables the quick decisions necessary to help achieve maximum yield potential.
The Plant Sap Potassium Meter
Potassium is often overused in contemporary horticulture, but tremendous amounts are utilised during the crop cycle, particularly with potassium-hungry crops like bananas and avocadoes. Potassium is the fruit-filler, and, if there is a potassium shortage during the fruit development stage, then ultimately yields will suffer. Conversely, excessive potassium ties up magnesium and boron, which can also negatively affect production. Once again, the balancing act can be quite difficult, but the Plant Sap Potassium Meter takes the guesswork out of potassium management.
The Plant Sap Sodium Meter
The increasing salinity of many irrigation sources and the build-up of sodium through the use of high-sodium chemical fertilisers can sometimes create plant health problems. The Plant Sap Sodium Meter can identify any potential problems at the onset. If sodium base saturation percentages exceed potassium base saturation in the soil, then the plant will begin to take up sodium instead of potassium. The Plant Sap Sodium Meter, used in conjunction with the Plant Sap Potassium Meter, can diagnose these problems early to allow rapid correction. Note: All three of the Ion Meters can also be used to measure soil levels of nitrogen, potassium and sodium.
Plant Therapy™ – Diagnostic Precision
Any of these diagnostic tools can be of tremendous value in monitoring plant nutrition, but the ultimate package for serious growers or consultants is the combination of all seven tools for a cross-referenced, more complete picture of crop requirements. A single squeeze with the NTS Sap Extractor can provide enough plant juice to fuel the analysis requirements of the Refractometer, Plant Sap pH Meter, Plant Sap Conductivity Meter, Plant Sap & Soil Nitrate Meter, Plant Sap Potassium Meter and the Plant Sap Sodium Meter.