The Major Benefits
Silicon is the second most abundant element on the planet, and yet the plant available form has become critically low in most of our farmed soils. All plants need silicon, all plants use silicon, but farmers using extractive farming methods haven’t been replacing it for a long time.
It turns out silicon is a key player in the immune response and the stress response, helping the plant to resist pathogenic attacks, pest damage, and harsh weather conditions. The first line of defence is the plant cell wall. Fungal pathogens use their hyphae to pierce through the wall and into the cell to feed and spread to other cells. Silicon forms much of the cellular structure, and when in abundant supply, will considerably strengthen this all-important front-line defence. Plants have even been shown to rush all available silicon to attack sites! High silicon content also increases the plants ability to cope with stressful conditions such as drought, heat and frost.
Magnesium and Calcium
Palagonite provides abundant magnesium and calcium as the dominant exchangeable cations, two key minerals in soil health. The balance between the two governs a soils ability to breathe, and support non-pathogenic aerobic microbial activity. Palagonite has been shown to have a flocculating effect. This means the balance is tipped in favour of calcium, which opens and softens the soil structure increasing the oxygen content and overall friability.
Calcium and magnesium also play key roles in plant health. Calcium is the king of plant health as it governs the transport and delivery of all other minerals. Calcium also plays a key role in the overall strength of the plant, particularly in yield, quality, size and shelf life. Magnesium is an essential driver of photosynthesis and chloroplast formation. Without it plants struggle to utilise sunlight and create chemical energy. Magnesium also promotes germination, early stage plant growth, and overall plant health.
Palagonite is a more cost effective, and superior alternative to the application of Dolomite or Lime. This is due to having calcium and magnesium as the dominant exchangeable cations, and a pH of 8-8.5. The other 20 essential nutrients are a bonus of significant value. Also, as an undesirable consequence, every tonne of lime applied results in 400kg of CO2 being released into the atmosphere. Palagonite is not just a rich source of silicon, magnesium, calcium and all the other equally important essential mineral nutrients that make up the composition of this unique volcanic substance. Palagonite also assists with several key functions in soil structure and health.
Cation exchange Capacity
The cation exchange capacity (CEC) is a measure of a soils ability to store and exchange positively charged nutrients, and is an important driver of fertility. The CEC value of most soils ranges between 10 and 25, while other crushed basalt rock dusts between range between 4 and 14.
Palagonite has a CEC of 34 and this is a significant advantage to soil fertility. The addition of palagonite to a soil will increase the capacity of the soil to attract and hold naturally occurring and applied soluble nutrients. It will reduce leaching and make these retained nutrients available to the crop, as required, to maintain optimal growth.
Palagonite has good levels of paramagnetic activity which has been associated with improved soil fertility in numerous ways. However, recent research in geomicrobiology has demonstrated that some soil microbes use magnetic iron particles in the soil as a battery with some species pumping electrons into the particles while others extract. Energy production through the exchange of electrons has long been known to be the driving force behind all life on earth. The abundant amounts of fine grained iron particles in palagonite can serve as conductors, sinks and sources of electrons for soil microbes, depending on their needs.
The ability of palagonite to hold significant amounts of water is a result of its large surface area, due to its largely amorphous structure, and non-swelling smectite clay content. This clay is unlike most smectite clays in that it allows water absorption and desorption without expansion or contraction.
In fact, palagonite can hold up to 40% of its weight in water without losing its fine granular consistency. This unique property will play a key role in repairing many of our damaged soils which have lost much of their ability to hold onto water, which allows leaching, and runoff of applied soluble fertilisers, and erosion of precious top soils.
Palagonite is also proving to be an effective microbial catalyst; this is most likely due to the broad spectrum of bio-available nutrients it contains along with the fine grained iron particles acting as both a source and receptor of electrons. In recent years interest in microbial soil life has surged, it has become increasingly apparent that microbes are essential to plant health and soil fertility. They are in fact, the power-house of the soil, - “Feed the microbes, to feed the soil” is now a common mantra. Palagonite is the ideal food source for soil microbes.
Composting with Palagonite
Composting is now a large part of organic agriculture. Compost provides a way to increase fertility, build organic matter, sequester carbon and boost the microbiome in farmed soils.
The addition of palagonite to the start of the composting process has a range of beneficial effects. Not only does this create a low odour, well finished product, that is rich in the full suite of essential nutrients that are now activated by microbial activity, the finished compost also contains higher levels of the volatile Nitrogen compounds (+20%), such as ammonia, that would usually have volatilised to the atmosphere during the composting process.
Combined with all of the other well-known benefits of compost, Palagonite increases the total essential nutrient and mineral content substantially. Composting with Palagonite is perhaps the most beneficial application as it creates a unique, and nutritious, complete organic fertiliser, with all the benefits of compost, and Palagonite, combined. Palagonite has also been shown to reduce the composting period from over 22 weeks to less than 15 weeks in commercial scale operations.
Palagonite has also demonstrated exciting properties in the areas of odour control, and waste management. The addition of palagonite to some of the more odorous and more difficult to compost organic waste streams is now being used to create rich, and complete, regenerative fertilisers to restore the soil fertility, and repair the damage done by environmentally destructive past practices.
In numerous field trials conducted with a range of crops since 2015, Palagonite has been shown to reliably increase yields (e.g. Ginger, more than 50%), and improve the quality and nutrient density of crops trialled. Reduced irrigation requirements along with less pesticide applications, due to a healthy crop and soil – has been shown to reduce crop costs, and increase bottom line profits.
Palagonite is by far the most cost effective soil repair tool available to the modern farmer today. As the atmosphere warms and the climate shifts, farming is only going to face more new challenges. Extreme weather, resistant pests, worn out soils and devastating diseases are now a fact of life in many parts of Australia. It is essential that our farming systems adapt and change to regenerative farming methods to become resilient and sustainable over time. This can only be achieved with a major effort by all stakeholders to remediate and re-mineralise our soils.