Why did Justus von Liebig believe agriculture needed scientific principles?

Justus von Liebig believed that a rational system of agriculture could not be formed without the application of scientific principles because he viewed perfect agriculture as the fundamental basis for all trade and industry.1

He argued that only a chemist possessed the necessary expertise to advise farmers on the most effective methods for feeding plants, identifying the nature of different soils, and understanding how specific manures interact with them. By applying organic chemistry to these processes, Liebig sought to replace traditional empirical training with a systematic, science-based approach to farming.12

Although some of his specific theories—such as his views on nitrogen sources and the efficacy of his early chemical fertilizers—were later proven incorrect, his work was instrumental in launching the agricultural sciences and shifting academic focus toward the natural sciences. His efforts ultimately contributed to increased food production during a period of significant industrial and population growth in Europe.21