Speaking at the recent Cork 2.0 European conference on rural development, Pauli said that the company he chairs, Novamont, now processes 360,000t of thistles at plants converted from former oil refineries. The weed is converted into lubricants, chemicals, plastics and animal feed.

"There is an enormous business model behind it, and the cost price is for free: you don't even need to buy seeds," he told the Irish Farmers Journal. "We are generating €3,700/t of thistles."

Listen to an interview with Gunter Pauli in our podcast below:

Pauli said the example of thistles should inspire us to look for alternative ways of generating value from agriculture. In his presentation, he gave other examples of agribusinesses thriving on this idea, which started when he first got involved in coffee farming. With only a tiny fraction of the coffee crop ending up in the consumer's cup, he looked for alternative income streams from the by-products and found that coffee waste was an ideal compost to grow mushrooms.

Today, some coffee and tea plantations Pauli invested in generate more cash from mushrooms than from their original product. He said this should question our habit of farming to produce only one type of food.

He compared the fate of specialised farming with that of pandas, which are facing extinction because they can only feed on shrinking bamboo forests. Instead, he said we should be imitating cockroaches, who "can eat anything" and will always be around.

Pauli is an enthralling public speaker and writer, author of the book The Blue Economy. Although his presentation makes farming for alternative value streams sound easy, he acknowledged that it took work from chemists to identify valuable molecules in thistles before they could be turned into a business. Converting former oil refineries into bio plants also came at a significant capital cost.

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