What does it mean to be regenerative?

Regenerative farming is a system of producing food and biomass that focuses on building functional biodiversity and soil health to produce consistent yields without relying on synthetic inputs (herbicides, pesticides, and chemical fertilizers). Despite growing interest in regenerative agriculture, there is no centralized “official” definition because regenerative agriculture is not a static state. Rather, regenerative agriculture is a journey that involves fundamentally changing our perspectives about nature and agriculture – in short, a shift in our mindset.

Through this lens, we see that regenerative agriculture is a way of moving from that extractive, reductive, and destructive form of agriculture and towards a sort of nutrient equilibrium – balancing multiple symbiotic life forms to create rather than destroy ecosystems.

Humans’ understanding of agricultural effects on soil health has dramatically improved, leading to the realization that monoculture with heavy inputs of pesticide and fertilizer is actually not a best practice in land management and is increasingly disadvantageous. You may fear that moving away from industrial agriculture and towards more regenerative farming in line with nature would lead to lower yields and fail to feed our huge global population. Recent meta analyses have identified that farm yield does not decrease in farms that prioritize biodiversity. Yet, there is a cost and time delay in the conversion of conventional and sustainable farming practices. What indigenous people with traditional knowledge have long known, is that soil fertility and functional biodiversity are the keystones of productive and regenerative farming systems.

Regenerative Farming in Practice

Regenerative farming, or farming in line with nature, also known as restorative agriculture or ecoagriculture, is a nature-based solution, and it is significantly different from organic farming. Organic farming focuses on removing synthetic pesticide inputs or replacing them with organic alternatives in otherwise conventional (often industrial) farming, then farms can be certified as organic. Regenerative farming, which does not have any formal certification, means rethinking the entire farm operation, building functional biodiversity by thinking of the farm as a landscape and building in elements to promote healthy ecosystems. There is no single pathway to regenerative farming. Some practices that you will see on regenerative farms are landscape elements (e.g. hedge rows with multiple species of bushes and shrubs), perennial rather than annual plantings, mulch and green manure covering any bare soil, and trees planted among the crops.

Creating permanent habitats on the farm provides homes for small animals like pollinators and pest predators. This creates a dynamic environment that can respond to stresses and is more resilient thanks to the diverse interlinking aspects of its food web. The same goes for the soil. When tilling is stopped, and the soil has constant vegetation growth, plant roots are able to provide homes to many microorganisms that provide nutrients, and fertility to the soil and the food. Regenerative agriculture is a mindset shift from extractive to restorative practices. It’s important that specific practices aren’t cherry picked but rather a comprehensive farm plan developed for this long term transition.

Five regenerative agriculture practices and their impact on the soil:

1) Cover cropping with green manure
Green manure is plant matter that is grown alongside the primary crop and provides multiple benefits. Not only does the cover crop bring diversity to the field which in turn can bring diverse pollinators and pest predators, but the cover crop is then incorporated back into the soil. This is a very direct way of regenerating soil, providing it with biomass to feed on and build itself up. Adding cover crop as green manure helps to increase the nutrient content of the soil, and the crops you plant and incorporate into the soil can be tailored to the nutrient needs of the soil.

2) Prioritizing perennial plants
Perennial means that the plant and its roots remain in the ground year over year instead of being pulled up after a season. Perennial crops, ground cover, and landscape elements provide a unique function for the soils. Soils are a living entity and roots that continue to inhabit soils year after year engage in more complex, symbiotic relationships with the organisms around them. Helpful fungi latch onto roots and provide communication channels and nutrient exchange for one another, bacteria develop nodules and provide services in the form of enzymatic reactions (i.e. converting nitrogen in the air to nitrogen in the soil), and the positive soil food web impact increase from there.

3) Minimizing/removing tillage
Tilling, or ploughing, soil aerates the upper layer of soil typically 20-50 centimeters in depth. Although in the short term, tilling facilitates easier planting, in the long term there is a critical loss of soil structure. Soil structure helps to retain moisture and allows drainage in the soil. Also, soil structure provides the scaffolding within which the soil food web thrives. Without this structure, there will not be significant life in the soil.

4) Reducing/removing synthetic inputs
Regenerative agriculture does not need to be a zero-input system, but rather a system where there is a net positive gain in soil generation. Pesticides are indiscriminate and kill not only the pest they are aiming at, but also similar organisms removing critical components of the soil food web. Soils become dependent on inputs of synthetic fertilizers and reduce their own capacity to circulate nutrients without these inputs. Slowly reducing synthetic inputs like pesticides and fertilizers allows the natural ecosystem in the soil to flourish.

5) Mulching with organic materials
Studies have shown that there can be incredible biodiversity in leaf litter layers as they slowly break down. Like green manure, mulch provides additional biomass to the soil to facilitate soil regeneration. Mulch also prevents bare soil, which prevents soil erosion

Why are companies transitioning toward regenerative farming?

No matter what product a farmer is producing, be it milk or kale, what regenerative land management systems have in common is that they protect against climate, supply chain, and regulatory risk. Soils are getting tired, and the current (industrial) farming models are not exactly profitable: last year 40% of farmers’ income in the USA came from government subsidies. By contrast, regenerative farming systems require fewer expensive inputs and often produce a wider variety of salable crops and byproducts. Not only is regenerative farming beneficial for increasing biodiversity and (environmental as well as economic) resilience, but the practices can also be used as carbon sinks, sequestering carbon in the soil. Many enterprising farmers are already accessing carbon credit markets by switching to regenerative practices. Moving from conventional agriculture to regenerative agriculture requires a mindset shift, and it is a shift we see happening at all scales all across the globe. The tradeoff in regenerative agriculture is that the systems are more complex to manage, but this does not translate into a reduction in yield. Most importantly, in the transition to regenerative agriculture, the benefits to human and environmental health are profound. 

On top of this, degradation can also lead to soils releasing their stored carbon as CO₂, amplifying the climate crisis. In 2015, when I spoke at the UN climate change conference COP21 in Paris, I warned of impending disaster if we don’t protect our soils from degradation with techniques which reduce soil erosion, such as planting cover crops.

At that time, I was described as a “peddler of university disaster pornography” by climate change deniers. But my testimony was not some fanciful prediction. As studying the dust bowl reminds us, the repercussions of soil degradation are still being felt today.

Degradation

Across the UK, soils have been degraded due to intensive agriculture, leaving them vulnerable to erosion by extreme weather. In the spring of 2014, when heavy rainfall across the UK saturated land, degraded soils were unable to store water, leading to widespread flooding and soil erosion. That month, the Earth observation centre NEODAAS in Plymouth released a satellite image of the UK “bleeding” its soils into the ocean.

Recent research at the universities of Sheffield, York and Leeds has shown how we might fix this problem: by using no or shallow ploughing, rotating land used for farming, and planting cover crops, all of which allow our soils to rest and recover. Coupled with limiting fertilisers, this allows populations of beneficial soil organisms like earthworms, fungi and bacteria to increase.

Regeneration

This evidence supports growing calls to embrace regenerative agriculture, which calls for supporting – rather than fighting – biodiversity within the agricultural landscape.

In South America, for example, the popular method of “slash, burn and move on” agriculture – where forests are felled, burned to release nutrients and then farmed until those nutrients are depleted – has been criticised for its destruction of biodiversity. In contrast, regenerative agriculture’s focus on increasing biodiversity has been shown to be a success in terms of protecting and even increasing soil health in the region.

Part of regenerative agriculture involves taking pressure off our soils, which might appear tricky in light of the need to feed a growing global population. Our research has shown that producing more food in the urban environment could help achieve this.

Crops can be grown in crowded cities using highly efficient hydroponic systems, which use less water, less fertiliser and require no soil. These can operate on top of flat-roofed buildings – or even in refugee camps, where farming enhances food security and community resilience. By growing crops close to where people live, we can remove the need to ship food around the globe, making our food systems much more sustainable.

Almost 20% of greenhouse gas emissions currently arise from agriculture: meaning that carbon is effectively leaking out of our soils across the world. That means we urgently need to embrace technologies that take a soil-centric view of food production if we are to leave a functional agricultural ecosystem for future generations.

We understand why this happens. Ploughing breaks down conglomerations of inorganic soil particles such as clay and sand, bound together by organic material such as dead roots, fungal filaments and bacterial and earthworm secretions. These store organic carbon and build soil structure. Without them, soils wash out more easily into our rivers and estuaries.

5 things you should know about earthworms

Aristotle called earthworms “the intestines of the Earth” and Charles Darwin was a fan, he wrote his last book about the humble earthworm just before he died. They are hermaphrodites with a crop and gizzard digestion system, similar to chickens, and there are between 10 and 400 of them in every square metre of soil beneath our feet [1].

Earthworms are vital to the structure and health of soil – they improve aeration and drainage, they feed other soil-dwellers with their poly-saccharide mucus (and moles in a more direct way) and they bring organic matter from the surface and integrate it into the soil. Emma Sherlock, the Natural History Museum’s worm guru calls them ‘little engineers’.

My fascination with earthworms started at an early age – I would have been eight or nine when my class teacher brought in a wormery to show us how they burrowed in soil. The wormery had a glass front covered with a wooden slide to keep the light out. When this slide was removed, we could see the tunnels made by the worms with trails of sand taken from the surface and down into the depths. I tried to make my own at home but the few worms that I imprisoned either escaped or died. An early lesson for me in the fragility of our natural world!

In honour of World Earthworm Day, we have gathered five facts that you may or may not want to know about the little engineers below our feet:

1. What is the biggest earthworm found in the World?

The Giant Australian Earthworm can reach 3m in length – imagine meeting that on a dark night? However, that is nothing to the South African Microchaetus Rappi that holds the official Guinness Book of Records title as the longest earthworm. In 1967, this specimen was measured at 6.7 metres long with a diameter of 20mm.

2. How much soil can earthworms (normal size) process each day?

Typical populations of earthworms can process about 5 tonnes of soil per year per hectare (about 2 tonnes/acre per year)

3. How quickly can they breed?

In good conditions, earthworms can lay about 10 eggs a month. With eggs typically having 10 baby earthworms inside, that results in one earthworm becoming 101 earthworms in a month! It takes sixty days for a worm to reach maturity so, at the end of three months, that one earthworm will have led to a population of 10,000 descendants, each one capable of doing the same thing for several years.

4. Why do you sometimes find worms tied up in knots?

When conditions are not right for worms, it’s too dry or too cold, they can enter a state of estivation (also known as a diapause). They turn off all unnecessary functions, tie themselves into a ball and cover themselves in a mucus that prevents water evaporation from their skin.

5. How long have earthworms been around?

About 209 million years is the best estimate [2]. That is about 35 times longer than humans who appeared on Earth a measly 6 million years ago.

I hope that you will start to think more about the earthworms moving beneath your feet next time you are out for a walk (especially if you live in Australia or South Africa)!

There are over 6,000 species in the World, some glow in the dark, some even climb trees. They can survive for a while in oxygenated water and, at various times in the last 209 million years, they have been aquatic.

Most importantly, we need them for healthy soil, without them and all of their microbial and fungal friends, soil is just dirt.

References:

[1] Lee, K.E. (1985) Earthworms: their ecology and relationships with soils and land use. Sydney: Academic Press.

[2] F.E.Andersen et al. (2017) Phylogenomic analyses of Crassiclitellata support major Northern and Southern Hemisphere clades and a Pangaean origin for earthworms. BMC Ecology and Evolution.

Scientists tell us that soil with a diverse microbial community promotes plant growth, while soil with more homogeneous microbial makeup suppresses growth.

Just like us, plants have a microbiome too. It is called the rhizosphere. It’s a narrow area of soil very close to the roots where bacteria and microbes influence plant growth and disease suppression.

Microbes work to convert nutrients into food for the roots to absorb, produce hormones that stimulate growth, prevent infections, filter out metals and contaminants from the soil and release nutrients. In order to have healthy plants and soil we need to put more microorganisms back into the soil.

For many years, the benefits of plant growth promoting rhizobacteria and mycorrhizal fungi in agricultural soil have been understood and we have developed products that combine those two key elements and apply them at the right place and concentration to accelerate soil regeneration.

Jeff Allen, Founder of Microbz says, “all of life came from this mantle of soil and we eventually go back to it. We have devastated the microbial life in our soils by overusing chemicals and intensively farming. But it isn’t too late to reverse this impact. We harvest beneficial microbes and put them back into degraded compacted soils to revive our dying land.”

Sign up to our newsletter on the website to get regular blogs and news about microbes in soils. In this blog we’re going to discuss microorganisms and how they work in soils, organic and regenerative farming, research, and what we are doing as a team to deliver probiotic solutions.