The permissibility of hydroponics in organic agriculture is a source of ongoing debate in Canada. Under Current standards, soil-less 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 standards clearly refers to soil as the required growing medium. However, no mention is made of the soil-less systems whether natural or artificial. [The current draft of the Canadian Standard prohibits hydroponic systems in greenhouse production.]
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.
At the core of the hydroponics 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 bacterial, 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 hydroponics growers are willing to sacrifice the sterile conditions they so enthusiastically promote.
“The lack of bacteria, fungi and other soil organisms contradicts what many believe to be the core values of organic.”
One reason hydroponics may be deserving of organic status is that crops like watercress and spirulina already grow naturally in soil-less systems. Another crop is Algae. In the 1970s, John Todd and the New Alchemists in both Massachusetts and Prince Edward Island 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 the 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 superphosphate upset the balance of the soil and eventually cause pests and disease problems no longer holds true. Moreover, if the system is closed phosphorus loading and potassium leaching in the environment are non issues.
It follows, then that is sterile hydroponic greenhouse operation become certifiable, then it should be permissible to use soluble phosphorus, 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 the 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 bio-diversity. 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 soil-less culture appear more organic than others. Some initiative is required in Canada to define the differences more carefully because the current standards are vague. A possible start would be to distinguish between cultures that do or 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 overreached the definition of organic. Are organic biofuels next?