Earthworms Make Light Work Of Soil Regeneration

With sugar cane being a perennial crop that is ploughed out and replanted only after a number of years, the soil in which it grows can suffer as a result of monocropping. KwaZulu-Natal sugar cane farmer Chloe Clegg has engaged earthworms to improve the health, productivity and sustainability of the soil on her family farm. Lloyd Phillips visited her operation near Harding.

When she joined her family’s farming operation in 2011, after qualifying with a BSc in conservation ecology from Stellenbosch University, Chloe Clegg brought with her a wealth of fresh ideas. These included improving on the production methods used by her father, Guy, in his many years as a sugar cane farmer on their 1 220ha of farmlands in the Harding and Hluku areas of KwaZulu-Natal.

Her ideas would complement Guy’s efforts to implement regenerative agriculture practices, such as developing a largescale vermiculture system.

“My father wanted to see if we could improve soil health and crop yield by applying more vermicast and worm tea and less inorganic fertiliser,” explains Clegg. “If it worked, it would also save us money because we’d need to buy in less inorganic fertiliser. And we have plenty of scrap sugar cane stalks and tops, as well as jungle wattle and bugweed, to use as food for the earthworms.”

Trials

Clegg was allocated the 824ha sugar cane enterprise to manage and soon thereafter made contact with Gary Farr and Stuart Lindsay of Regenerative Agriculture Specialization, based in Pietermaritzburg. In particular, she sought their guidance on what regenerative products and practices would work synergistically with vermicast to improve sugar cane soils’ biology and productivity.

“My father and I used to apply CMS [concentrated molasses solids], a by-product of the sugar cane milling process, to the sugar cane as a base organic soil nutrient. We then supplemented with inorganic fertilisers. But we found it challenging to manage CMS application rates and times. The Glen Rosa and Dwyka soil types that are common across our sugar cane fields are not naturally fertile and productive. So we agreed that we’d start trialling granular fertilisers complemented by the worm products to boost soil and crop productivity,” she says.