Learning about regenerative agriculture

The implementation of regenerative agriculture principles is allowing a growing number of farmers to reduce their inputs while producing similar or even better yields than they would have produced if they used conventional farming practices.

regenerative agriculture tractor ploughing
The aim with cover crops is to create as much diversity as possible.
Photo: Buz Kloot

Regenerative agriculture is the latest buzz in responsible agricultural management. It is similar to conservation farming in that it combines the use of stubble retention, crop rotation and the minimum disturbance of the soil to promote soil health, but is on a higher level as it also incorporates the use of cover crops, compost teas, compost and manure (to avoid using synthetic fertilisers), pesticides and genetically modified organisms (GMOs).

While having the same aims, it moves beyond the simple definition of ‘organic’ and ‘biological’ production, aiming not only to replace chemical inputs with so-called natural inputs, or to improve microbiological diversity, but to adapt farming practices to what is happening in and around the plant, and to essentially mimic rather than work against nature.

The first thing to change when switching to regenerative farming is your mindset, says Prof Buz Kloot from the University of South Carolina in the US. Kloot, a proponent of regenerative farming, has been documenting regenerative farming practices in the US since 2011.

During a recent regenerative farming conference in Cape Town, he explained that farmers are often led to look for quick fixes to improve production outcomes.

Regenerative agriculture, in contrast, is built on a “soil health mindset”, which is “more about thinking through what you are doing and where you are going with your production practices”.

It is based on the understanding that soil is a living, dynamic ecosystem and not just a growth medium. “Soil health, in effect, should be seen as a journey and not a destination, with production strategies continuously being adapted to accommodate changes in the system.”

It is also not about equipment, but about understanding how systems work.

Agriculturefixes to improve production outcomes. Regenerative agriculture, in contrast, is built on a “soil health mindset”, which is “more about thinking through what you are doing and where you are going with your production practices”.

It is based on the understanding that soil is a living, dynamic ecosystem and not just a growth medium.

“Soil health, in effect, should be seen as a journey and not a destination, with production strategies continuously being adapted to accommodate changes in the system.”

It is also not about equipment, but about understanding how systems work.

Kloot says regenerative farming proponent Ray Archuleta taught him that equipment, such as no-till planters, was important, but just “one of the types of tools available in the quest for better soil health”.

The practice
Jason Carter, a farmer from the US who seven years ago started using multispecies cover crops with chicken manure as his primary source of fertiliser, says increased awareness of the importance of soil health has led to “farmers no longer boasting about the size of their tractors, but the size of the radishes in their crop mixes and the carbon content of their soils”.

Carter farms in Eastover, South Carolina, in a region that receives more than 1 000mm of rain a year. With its very sandy soils, the region, in spite of high rainfall levels, is always “two weeks away from a drought”.

The cover crops he uses to ensure there is always a crop in the land consist of a mixture of rye, radishes, clover and vetch before he plants maize. Rye, radish and lupin are planted before cotton or soya bean.

Carter, nevertheless, wants to expand his cover crop mixtures to at least eight different species, since the general consensus is that the bigger the diversity, the better aboveground biomass, soil health, and consequently, soil fertility.

It cost him about R850/ha to establish the cover crops. “You can let the weeds grow if you do not plant cover crops. While this is not ideal, it is better than having nothing.”

During the first year of using regenerative agricultural practices, he chemically terminated the cover crops almost two months before planting his cash crop.

He realised, however, that this resulted in him not leveraging the full benefit of these crops, so he now only sprays cover crops before planting soya bean, and plants his maize into green covers.

“The cover crops planted before soya bean, usually 30 to 40 days after maize, are sprayed 30 days before planting to ensure there is enough moisture in the soil for soya bean production and because soya bean needs good seed-to-soil contact,” he says.

Fertiliser savings
As is the case with many other farmers using regenerative agriculture, Carter’s achievements are exposing a few anomalies in traditional farming practices.

For example, he has eliminated the use of granular phosphorous and potassium, without any impact on production, crop quality or his soil test results. Instead, he applies 1t to 2t of chicken manure when planting cotton and maize, and no manure when planting soya bean.

While general consensus in the US is that at least 1kg of nitrogen is needed to produce 55kg of maize, Carter produces 11,5t of maize for 50kg nitrogen applied to his dryland maize, which is 230kg maize per kilogram of nitrogen.

He applies half of the 50kg/ ha as slow-release nitrogen to his dryland maize, and adds another 50kg of liquid nitrogen to his irrigated maize through the pivot.

He achieves about 15t/ ha of maize under his irrigation system for 100kg/ha nitrogen.

Many cover-cropping farmers in the southeastern US, including Carter, have also seen that they can get away with less or no lime despite the traditional conviction that lime should always be applied to counter the acidification of soil.

Kloot says that in some parts of the US, farmers apply up to 2 100kg/ha of lime every second year, at a cost of about R1 850/ ha. “We, however, have seen that despite the use of no lime, we are actually seeing an increase in pH levels where we are cover cropping.”

One of the reasons for the positive results with cover crops is that crops with deep root systems help to bring soil nutrients to the top layer of the soil.

“Farmers usually take soil samples at a depth of 15cm, yet soil nutrients such as phosphorous and potassium generally reside much deeper. By reducing the volumes of fertiliser needed to correct deficiencies, cover crops with deep root systems can generate savings equal to a pension plan,” he says.

Better soil structure
As has been found with conservation farming in South Africa, regenerative agriculture is buffering production against droughts and floods and protecting the soil against water and wind erosion by improving the soil structure and resilience.

To illustrate, Carter managed to produce 5,3t/ha of maize in spite of an extreme drought at the start of 2015, while neighbouring farms using conventional methods abandoned their fields and collected the insurance.

Later that same year, his farm was flooded, with 508mm of rain falling in less than 24 hours.

In spite of most of his neighbours suffering severe crop losses, he was still able to harvest a soya bean crop three weeks later.

“The harvest was only a third of our normal production, but still better than nothing. We also did not suffer severe soil loss, whereas most of the topsoil of one of my neighbours ended up in one of my fields.”

Although Carter primarily makes use of minimum and no tillage, he was forced to strip-till the lands that were flooded as there was a great deal of compaction. “Regenerative farming is not set in stone. You need to use common sense and adapt your strategies to what is happening in the land and with the plant.”

Pest management
While conventional farming teaches that ‘the only good bug is a dead bug’, regenerative farmers recognise the benefit of having a huge diversity of soil microorganisms – ‘good guys’ or ‘bad guys’ – to create a healthy, balanced ecosystem, and the positive spin-offs this has for pest management, pollination and the breakdown and binding of minerals.

Pesticides are used as a last resort; Carter has over time been able to reduce his pesticide usage by 70% and fungicide usage by 95%. He plans to completely phase out the use of pesticides, seed treatments and GMOs.

Cover crops ensure a beneficial habitat for the soil organisms through the creation of above- and below-ground habitats for beneficial microbes and invertebrates.

A good foundation
Kloot says one of the reasons producers’ experiences are not in line with the conventional agricultural production model is because most conventional agricultural science is done on degraded lands.

Research conditions, in effect, are not representative of what is happening in healthy soils, where farmers use minimum tillage, cover crops, stubble retention, organic sources and reintegration of animals to build soil biology.

Kloot advises farmers to convert slowly, and grow with the system: “The switch should be well planned and founded on good production principles, otherwise you will run into problems.”

Email Buz Kloot at [email protected] or Jason Carter at [email protected]