For over three decades, the California Agricultural Experiment Station has conducted investigations of problems of plant nutrition with the use of water-culture technique for growing plants, as one important method of experimentation. The objective has been to gain a better understanding of fundamental factors which govern plant growth, in order to deal more effectively with the many complex questions of soil and plant interrelations arising in the field. Many workers have participated in these investigations. One of them, Dr. w. F. Gericke, conceived the idea some time ago that the water-culture method, hitherto employed only for scientific studies, might be adapted to commercial use, and proceeded to devise special technique for this purpose.
In the nineteen thirties, this development was given widespread publicity in newspapers, Sunday supplements, and popular journals. The possibility of growing plants in a medium other than soil intrigued many persons, and soon extravagant claims were being made by many of the most ardent proponents of the commercial use of the water-culture method. Furthermore, amateur gardeners sought to make this method a new hobby. Thousands of inquiries came to the University of California for detailed information for general application of the water-culture method to commercial as well as to amateur gardening.
Because of doubts expressed concerning many claims made for the use of the water-culture method as a means of crop production, it became evident that an independent appraisal of this method of growing crops was highly desirable. I therefore requested Professors D. R. Hoagland and D. I. Arnon to conduct certain additional investigations and to prepare a manuscript for a popular circular on the general subject of growing plants in nutrient solutions.
When this circular was first published in 1938, neither the California Agricultural Experiment Station nor the authors made any general recommendations as to the use of soilless culture methods for commercial crop production. The purpose of the publication was to make available such technical information from the researches of the Station to those who wished to experiment with the waterculture method on their own responsibility. An attitude of caution and a balanced consideration of the various factors determining success in growing crops on a large scale, whether in soil or in nutrient solutions, was commended to the attention of those contemplating commercial ventures. The purpose of this revised publication and the point of view of the Experiment Station remain the same today. The experience of the past decade, during which a number of large-scale installations for soilless crop production was established in the United States and overseas, fails to support the exaggerated claims of the early enthusiasts of the technique.
[EBOOK] The Water-Culture Method for Growing Plants without Soil, D. R. HOAGLAND and D. I. ARNON, THE COLLEGE OF AGRICULTURE UNIVERSITY OF CALIFORNIA - BERKELEY
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