Consulting in Hydroponics

A while back, I expanded on a Wikipedia "stub" for Pythium spp. (a pathogenic organism that's commonly found in field and hydroponic crops, which principally affects the roots). Naturally, I was interested in finding out what others had to say in Wikipedia about hydroponics, and posted a few comments on hydroponics in general. Someone doing a bit of home hydroponic gardening from his windowstill wondered about a few things relating to temperature and the strength of his nutrient solution. Those questions and my answers can be found in my other blog Plant Doc, What's Up?.

Interestingly, the question of hydroponics has popped up fairly often when I talk to people with greenhouses in Eastern Ontario. Is it worthwhile? Is it practical to implement up here (as opposed to Southern Ontario)? To these people, I just had to point out that the reason why it's a booming enterprise in Southern Ontario, especially in the Leamington area, is due to the Lakes Effect. The Lakes Effect is a broad term describing the patterns of weather and temperature in the area proximal to one or more of the Great Lakes - in general, the temperature does not fluctuate to extremes within a short span of time, but rather takes longer to decrease/increase. In terms of your greenhouse heating/cooling costs, this is a bonus. The water temperature of hydroponic nutrient solution is also more easily maintained. (The implied additional advantage here is the proximity to large volumes of replenishable water, although hydroponic outfits such as SunTech Greenhouses just outside of Manotick make do with their proximity to rivers branching off the Rideau River)

A study investigating benefits of hydroponics in more northerly climes (see the August 2006 issue of Greenhouse Canada) suggests that while hydroponics can be productive enterprises, a variation called aquaponics has the potential to yield significantly higher revenues (subject to a cost-analysis study). All aquaponics is, is the combination of hydroponics with fish farming, which is now more feasable, thanks to new microbial technology developed at Brooks (although I pause to wonder whatever became of a similar project undertaken by Drs. Mike Dixon and Geoff Waters at the University of Guelph). Although the plant yield is significantly higher, aquaponics offers the added bonus of fish production - in essence, one system gives two yields.

Clearly, temperature and water inputs are important considerations, however, sunlight is also important. The slightly lower yields commonly seen in hydroponic operations the further north you go is most likely due to decreased direct sunlight and shorter days. Most of this can be mitigated with the use of extended daylengths provided by lights, but the Brooks research certainly implies that nutrition plays a key role in the productivity of the plants. The nutrients in fish wastes are made available to the plants through the addition of microbes to the water. Clearly, the composition and strength of these nutrients in the water is a key factor in aquaponics' performance over straight hydroponics, which utilizes chemical fertilizers made available to plants through a regime of strict pH monitoring.

Not to make this posting overly long, but the same independent greenhouse operators look south and see their Leamington counterparts reaping the benefits of government programs, extension and government specialists, free programs and collaborative research with universities (i.e. the University of Guelph or the University of Western Ontario)... so they feel neglected. I asked whether there were extension specialists or OMAF workers dealing with greenhouse crops in Eastern Ontario - and the answer was, "If there is, I don't know." In fact, one grower gets most of his information from two or three others in the Montreal/Laval area (who in turn obtain most of their extension from Laval/McGill or from the BioDome in Montreal proper). Another grower commented that there used to be a greenhouse program operating out of Kemptville College, but doesn't know what happened to it. Even though many operate fairly close to sources that should provide these services in Eastern Ontario, they do not routinely ask for them, because they can't find them.

I should point out that this is all hearsay; I am in the process of investigating the comments of these growers more thoroughly and will post updates (and of course, retractions/clarifications, if one or more comments posted prove to be incorrect). As always, people talking to me and providing comments will never be identified on this blog, or elsewhere, without their express approval. Interested parties may email me at nathan.owengoing@gmail.com.