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Can a regenerative farm avoid fertiliser?





One of the most prominent claims today in the modern surge of environmentally friendly and regenerative farming, is the belief that farms will exist without fertilisers from an external source?

A fertiliser is a substance that can be applied to the soil which has mineralised nutrients in a form that plants can easily use to help them grow and thrive.


While it is possible to use fertilisers from a sustainable and renewable source, farming without any fertiliser at all, naturally sourced or fossil fuel based, would likely lead to poorer quality farmland and reduced yields year by year. The main reason for this, is the energy leak in the farmers physical produce, animal or plant.



The 100% grass fed farming model example


A hypothetical 100 acre grass fed cattle farm is selling 20 cattle per year, with 20 new ones born and growing all on the farm.


The cattle grow and produce manure as waste energy which fertilises the soil they graze from, helping new grass to grow back between grazing.


However, every year there is 20 cattle with approximately 12,000Kg of nutrients leaving the farm every year in the form of meat, fat, bones and skin. And with a 100% grass fed system, the cattle only take energy from the localised area -the farm.


For example, if you were to eat one of our grass fed rump steaks, all of that nutrient dense beef we so often promote has originated from the soils of one of our suppliers farms. That energy is not easily returned.


But despite this loss, it is how a farm regenerates its nutrients is what is important to us, plants (namely grasses in this case which our cattle require) require three primary nutrients to live...

-Nitrogen

-Phosphorus

-Potassium


Nitrogen, the main and most important building block of a healthy soil, can be the most easily recuperated within regenerative farming. Plants such as clover and various beans take nitrogen directly from the atmosphere and store it useful forms in buds in their roots.


This is the perfect example of building soils without the use of fossil fuel-based fertilisers, the almost unlimited supply of nitrogen (78% of proportion) in the air is a fertiliser that could easily be used and therefore is “emission free”. Herbal Leys are pastures full of a diverse mix of herbs, grasses and legumes with clover often being in high proportion, these are a great addition to many farms looking to improve the quality of the fields which also makes the animals diet healthier too.

Phosphorus and Potassium are where things get more difficult. How could a regenerative farm regain these inputs that are lost within the bones and muscle tissue of the animals that leave their farm. While trace amounts of phosphorus and potassium fall in the rain, or run off from neighbouring soils, the impact will likely never be enough.


clover rich pastures



A regeneratively farmed solution?


The logical approach would be to retrieve the bones and muscle tissue, and (although not nice to think about) would be predominately through the use of human manure, a powerful but mostly unused fertiliser.


Human fertiliser is something not widely used due to the treatments that are used, particularly where it would become so toxic it would only reap negative effects on the land as opposed to any positive ones, potentially creating a risk to human health. Some countries where artificial fertilisers may be out of the question due to economic reasons, will often use human fertiliser. Countries such as Kenya and China use human waste as fertiliser.


However for centuries, human waste has been used as fertiliser, and it's not surprising why. While fossil fuels had not been utilised beyond 100 years ago, there would have been a shortage of fertile ground if this fertiliser from the rapidly growing human population had not been made use of.


It is also important to think about where large amounts of processing are used, that no waste from butchers, such as bones and blood from butchers are sent to landfill where the useful potential fertiliser would be lost to contamination, instead it is of great importance waste animal products are recycled to be used as a sustainable fertiliser, particularly regenerative farms that want to keep a low input and chemical free approach to the future.


Is the animals manure enough fertiliser alone?


Animal manure is a vital part of the cycle of life on pasture. The consumption of grass transforms the nutrients found in vegetation into a mix of mineralised nutrients that new plant roots can readily grow from.


If the pasture was not managed at all and the plants were left to rot without being digested first by our animals, although the top layer of vegetation would eventually compost itself, the process would be most probably too slow and lead to stagnant infertile ground, likely succumbing to brambles and weeds which happily move onto poorer quality soils.


Our livestock manure would be fine as the only fertiliser, only if the animals that grew on the land died and were left to rot back into the soil. As humans take the meat away to eat, we are taking that energy, hence the need for human manure fertiliser in a textbook case.


Where we have arable crops growing, and the energy removal is via vegetables or grains, the fertiliser need is generally a lot more intensive without animals manure freeing up the soils minerals. Which is why many mixed arable and livestock regenerative farms will rotate which fields produce crops, and which produce meat/milk to balance the nutrients across the farm. Yet the net nutrience is still in a deficit, but how much depends on the intensity of the farming. It is likely it could be many years before a decline was noticed just through physical energy loss.


grass fed heifer at horner farm


What about pasture raised chicken and pork? How this is different...


When we think about pasture raised chicken and pork? The calculations are slightly different. Why? Because pigs and chickens are always fed supplementary feeds within their natural pastured diet. And unless those feeds are grown on the farm, there is an external input. Any wheat, barley etc that are consumed by the pigs and chickens are effectively turned partially into energy for the pig to use to grow and exist, with the waste as fertiliser via manure.


Therefore, it's possible that pigs and chickens could exist on a farm that does not add fertiliser if enough of their diet was sourced from other farms crops. However, we are only depleting another farms nutrient value.


It can be thought of that a large area of farms, there will be years where some farms are in a nutrient deficit, and some within a nutrient excess, but by balancing and ensuring that what we consume is returned to the soil, regenerative farms are able to bring our farmland back to its optimum state.




The Future of Farming


Part of the reason truly regeneratively farmed produce comes across more expensive is due to the higher cost involved in using greener fertilisers, as well as running a lower output system that is less intensive on the land. However over time with rising oil prices, farmers may find this is the cheaper option to run their farm, forcing a more sustainable way of food production.


So, in conclusion? A regenerative farm may well have to use fertiliser to replace lost phosphorus, potassium and many smaller macro nutrients depending on the speed of their energy leaks, but depending on their current soils, it would likely be up to 100 years before the land had been mostly depleted. However, sourcing from sustainable sources is key for the environment and avoiding anything derived from fossil fuels.


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