Are organic and hydroponics a good fit?

By Rupert Jannasch, M.Sc.

The permissibility of hydroponics in organic agriculture is a source of on-going debate in Canada. Under current standards, soiless culture appears not to be permitted, but some intriguing questions need answers in order to bring clarity to the issue.

A loophole under the 1999 Canadian National Organic Standard made hydroponics permissible (depending on the certification body) because guidelines for greenhouse production did not explicitly state production must be soil-based.

The 2006 standard clearly refers to soil as the required growing medium. However, no mention is made of soiless systems whether natural or artificial.

The National Organic Program in the U.S., on the other hand, permits hydroponics. A considerable volume of literature on the Internet, mostly American in origin, accepts, without question, that soil-less culture is simply a variant of organic farming. This mind set appears increasingly pervasive among would-be producers.

At the core of the hydroponic question is the lack of microbial activity. Conventional hydroponics relies on special formulations of soluble fertilizers similar to those used on field crops. Most so-called organic hydroponic operations choose from an extensive list of concentrated nutrient solutions approved for organic production. The goal with either method is to keep the production space largely sterile.

The lack of bacteria, fungi and other soil organisms contradicts what many believe to be the core values of organic. If intense biological soil activity is said to be the cornerstone of organic farming, how can a production system that prides itself on being sterile fall under the same umbrella?

Elaine Ingham of the Soil Foodweb (www.soilfoodweb.com) has proposed a solution to the microbe shortage by adding compost tea to the nutrient broth. If effective, including a microbial stimulant might make hydroponics more palatable to regulators. What is not clear is whether hydroponic growers are willing to sacrifice the sterile conditions they so enthusiastically promote.

One reason hydroponics may be deserving of organic status is that crops like water cress and spirulina already grow naturally in soiless systems. Another crop is algae. In the 1970s, John Todd and the New Alchemists in Falmouth Massachusetts grew algae in translucent, above ground tanks. They were growing feed for fish. Could the algae not have been certifiable? The fish could have.

The fact that hydroponics can be environmentally benign poses a special problem for regulators. Consider that hydroponic systems can be closed with the exception of added nutrients. With total control of fertility in the hands of the operator, it is said that optimal nutrition for the crop is attainable. Perfectly healthy plants should be the result.

The problem with this scenario is that the prohibition against many conventional fertilizers in organic farming becomes irrelevant. The claim that fertilizers such as muriate of potash and super phosphate upset the balance of the soil and eventually cause pest and disease problems no longer holds true. Moreover, if the system is closed, phosphorous loading and potassium leaching in the environment are non-issues.

It follows, then, that if sterile hydroponic greenhouse operations become certifiable, then it should be permissible to use soluble phosphorous, potassium and perhaps even nitrogen amendments. To purists, this logic may seem blasphemous, but it does present a real risk. Inconsistent standards provide fertile ground for commercial interests to whittle away at the regulations and demand that conventional fertilizer be allowable in organic hydroponic culture. And that might only be a start.

Other environmental arguments become more abstract. From a stewardship point of view, hydroponics could be said to conserve soil because land can be spared from the plough. The same reasoning could favour biodiversity. If more food were grown in artificial environments wild plant and animal life might flourish on land no longer used for agriculture.

Clearly, some forms of soiless culture appear more organic than others. Some initiative is required in Canada to more carefully define the differences because the current standards are vague. A possible start would be to distinguish between cultures that do and don’t include microbial activity.

The prospect of attaching an organic label to hydroponic products presents an enormous marketing opportunity for growers and marketers. Yet at some point inclusiveness may begin to dilute the integrity of the product. Already some consider that organic textiles, organic body care products and organic aquaculture have over-reached the definition of organic. Are organic biofuels next?

 

Rupert Jannasch, M.Sc., P.Ag. is a consultant for the Organic Agriculture Centre of Canada. Views expressed in this article are not necessarily those of the OACC. Please send comments or questions by phone to 902-893-7256 or by email to oacc@nsac.ca

 

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Posted March 2008

“We gratefully acknowledge funding support from Agriculture and Agri-Food Canada for for production of this publication. Agriculture and Agri-Food Canada (AAFC) is pleased to participate in this project. AAFC is committed to working with industry partners to increase public awareness of the importance of the agriculture and agri-food industry to Canada. Opinions expressed in this document not necessarily those of the OACC or AAFC.”