Guano Organic Fertilizer News

Essential plant minerals

Learn from agronomist Robert Drewitt BcSc(Ag) why phosphorus [P] is so important to plants and how seagull guano helps ensure minerals are plant available.

Essential Plant Minerals

Article 2 of 12 - written by Robert Drewitt BcSc(Ag) | Agronomist | Agronomy Services Australasia Pty Ltd.

© Copyright in this work is owned by Guano Australia Pty Ltd. All rights reserved.

In the last article we went over some of the long history of guano and guano mining around the world, it showed how important as a fertiliser guano was for hungry Western countries feeding increasing populations. The demand for bird guano and especially the sea bird guano from coralised island and archipelagos was increasing as the need for phosphorus as a fertiliser increased. Mono cropping and the push for ever higher yields was seeing a reduction in agricultural output. By 1872 soil testing had started and by 1894 the Chemical Society of London had published an article called “Mineral Plant Food in the Soil”.  Scientists could now measure the minerals in the soil and for the first time the Agricultural Industry had a means to take the science and apply that to the soils; this saw the start of Agronomy, a branch of science.

The need for phosphorus [P] as an essential plant mineral had led to John Bennet Laws to patenting, in 1842, the first Superphosphate. He had discovered that by applying sulphuric acid to manure and observed that the b product gave quicker plant response to fertilising than manure alone. What he had discovered was the complex relationship between inorganic and organic fertiliser on crop yields.

Back to our guano story; John Laws’ work led to sulphuric acid being added to ground-up ancient guano bird deposits and as a result the modern product of Single Super Phosphate was discovered and commercialised. This fertiliser process saw a boom in factories including those near Australian on Nauru and Christmas Island.

So why is phosphorus [P] so important to plants? P is essential for all living organisms; plants require P for normal growth. It has an important role in respiration, cell enlargement, cell division, energy storage and photosynthesis. In a natural environment P comes from two sources; phosphorus salts are released from rocks by weathering and dissolved in water to be absorbed by plants and, the decay of organic matter that releases organic phosphorus, compounds the move down the soil profile and are available to plants after microbes, mycorrhizae and plant root exudates produce enzymes and organic acids that mineralize plant available P from organic and inorganic forms. 

Seagull guano, in its raw state contains citric and non-citric soluble phosphorus as well as calcium and silica. The unique interaction of these minerals in the guano have a lot to do with how the mineral including phosphorus becomes plant available while not being as vulnerable to being “tied up” or leeched from the soil. 

< Return

Have a question? Ready to place an order?



Being so far away from our markets, durability is critical and the Silica is really good in terms of hardening up the skin and making the melons better to transport.Ord River WA irrigator David Menzel-Barradale
The problem with many organic fertilisers is that they have very low rates of nutrients, meaning you need to put out high rates. A product like Guano Gold has 12pc P, whereas Guano Sulphur Gold has 10.5pc P, obviously with additional sulphur. These figures compare very favourably with something like a single superphosphate product. Agronomically, it’s a good product in any setting, not just for organic producers.Garry Allison, Landmark Agronomist. Mount Gambier, SA
For the broadacre croppers, Guano Gold works really well in paddocks where they have had issues with nutrient tie-up. He said the majority of synthetic P products have large rates of water soluble P. The problem with that is that you can have instances where it ends up tying up zinc in the soil so you run into problems with zinc deficiencies. Not only does the slow release nature of the Guano Gold product work well over the entire season, it also contains zinc for the crop as well as the other nutrients.Moree agronomist Rob Drewitt
We strongly recommend the Guano Gold products to fellow farmers if they are looking at improving their Calcium and Silica levels using various methods of application such as foliar and granular.James and Aimee Thomas Falkirk Macadamia Farm
I have recommended Guano Gold products for 20 years and in all cases had excellent long-term results increasing in pasture productivity.Paul Baguely - PB Ag Consulting
They are high analysis products so you get your nutrients without having to put too much fertiliser out.Anthony Beutel, Googa Farm Organics
We have known since the 1930s that phosphorus is one of the main elements required to grow a successful crop of not just the (flax) plant but the seed. It was one of those products that was first out in a granular type form and it was so much easier to get an even coverage over the ground, rather than a powder form. Later on the product became a little more refined, so we could put it through our air-seeder. We also broadcast some of it, prior to seeding, when we are cultivating ground. The products have great characteristics in relation to phosphate and silica, which is exactly what we need for flax.Waltanna Farms flax-seed farmer & Ambassador for Guano Australia, Michael Nagorcka

Read more testimonials