Revisiting the original reasons for excluding inorganic fertilizers in organic farming—Why the ban is not consistent with our current scientific understanding

Holger Kirchmann

doi:10.1177/00307270211020025

Abstract

This paper reviews the original reasons of the organic farming movement for excluding mineral (inorganic) fertilizers. In this paper, their theories and decision criteria for excluding use of inorganic fertilizers in crop production were revisited. Original reasons for banning inorganic fertilizers were subjected to scientific scrutiny, which was not possible when they were formulated 50–100 years ago due to limited knowledge of the soil-crop system. The original reasons were as follows: Rudolf Steiner, the founder of biodynamic farming, played down the physical role of plant nutrients and pointed out “flow of forces” as being most important for soils and crops. Eve Balfour and Albert Howard, founders of the Soil Association in England, claimed that inorganic fertilizer increases the breakdown of humus in soil, leading to a decline in soil fertility. Hans-Peter Rusch, the founder of biological organic farming, considered inorganic fertilizers to be imbalanced products not matching crop composition and not in synchrony with crop demand. When testing these historical statements as scientific hypotheses, older and modern scientific literature was used for validation. Steiner’s belief about the “flow of forces” has not be verified using current methodologies. The claim by Balfour and Howard that inorganic fertilizers accelerate soil organic matter decomposition is not substantiated by data from long-term field experiments on carbon and nitrogen cycling in soil-plant systems. The statement by Rusch that inorganic fertilizers supply crops inappropriately is difficult to uphold, as the composition, time, and rate of application and the placement of fertilizer in soil or on foliage can be fully adapted to crop requirements. In light of accumulated scientific evidence, the original arguments lack validity. The decision to ban inorganic fertilizers in organic farming is inconsistent with our current scientific understanding. Scientific stringency requires principles found to be erroneous to be abandoned.

Highlights

Exclusion of inorganic fertilizers is often perceived as a quality-improving principle that makes organic farming superior to conventional agriculture
The analysis consisted of the following steps: First, original statements by the initiators of biodynamic farming (Steiner, 1924), the Soil Association (Balfour, 1943; Howard, 1940), and biological organic farming (Rusch, 1978) were identified and cited
Organic farming was founded on the doctrine the inorganic fertilizers should not be used, in the belief that they are harmful for soil, food quality, and human health

Summary

Introduction

Exclusion of inorganic fertilizers is often perceived as a quality-improving principle that makes organic farming superior to conventional agriculture. Inorganic fertilizer cannot mimic the natural Principles observed in nature must guide Human activities should supply of nutrients by soils, so crops are fed agriculture. A living soil and “living forces” were singled out as being most important for crop production, while inorganic fertilizers were identified as being responsible for quality deterioration not providing “living forces.” The term “living forces” was explained by Steiner as forces surrounding organisms.

Results

Conclusion