WEEK 13 - "Gardening requires lots of water. Most of it in the form of perspiration." - Lou Erickson

If you step back and think about this question, "what is needed for ____ to thrive?" and you meet all the listed needs, it will thrive!  When I was in the first grade, I had the incorrect believe that plants needed soil to grow.  Without soil, how could a plant grow...correct?  In reality, that is not true.  Plants need several things to survive: sun, carbon dioxide, water, micronutrients (vitamins/minerals) and physical support.  Yes, soil can provide support and contains many micronutrients.  However, the knowledge of what is truly needed to survive is the key to meeting a plant's needs and ensuring rapid and healthy growth.  

photo taken by Toni on her tour of the hydroponic greenhouse

This has been a sabbatical of exploration.  I have read, garnered excitement and gone to "check it out" in the real world.  My last trip, I decided to check out growing practices in the Southeast including hydroponic growing and citrus farming. 

Curiosity and need drive invention!  Publications on the topic of hydroponics date as early as the 1600's.  In the 1930's at the University of California (Berkley), William Frederick Gericke began investigating the topic in detail and published The water-culture method of growing plants without soil.  The paper continued to challenge the thought that soil was required for a plant to grow.  As the years passed, people traveled more and lifestyles changed, people across the globe wanted their fresh vegetables.  But, what were they to do in places such as the beaches near the Pacific Ocean?  There is little to no soil in that region...but, lots of sand to provide physical support.  It was found that if they infused the water with the needed vitamins and minerals, the plants were able to thrive and produce. 

Experiential learning at its best (I even got to eat some of the produce on the tour)

I had the luxury and pleasure of visiting a hydroponic growing greenhouse that had been open for over 30 years.  If you think about it, there is no way to meet the plants' growing needs with distilled water.  When the water is distilled, it simply does not have the vitamins and minerals needed for optimum growth.  Through research, it was discovered that a solution water solution containing a variety of elements and compounds can be formulated and provided to the plant for growth.  

Nutrient solution chart

I was astounded and impressed when I saw the different types of physical support available for the plants if a farmer were to think outside of the box.  

Trellis for support

Sand for support

PVC for support

While on the tour, I kept thinking back to prior questions that caused me pause in my professional career.  I am often asked to describe the differences between a variety of growing practices such as modern/traditional, organic, and hydroponic.  As a follow up question, people often want me to make a judgement call as to which is "best".  Let me start by clarifying what each of the terms actually means.

Citrus farming in the Southeast

• Modern/traditional agriculture often makes use of hybrid (mixed or modified) seeds.  Advanced equipment is used to help the plants grow to their genetic potential with large yields.  Water irrigation, fertilizers and pesticides are used to give the plant an advantage in the field.  When people think of modern agriculture in the  Midwest, they often think of rows of corn or soybeans.  In the Southeast, someone may think of citrus groves.  Both of these are great examples of modern agriculture.
• The term organic has a specific and approved definition.  Most generally, it can be understood that, organic food is produced by farmers who emphasize the use of renewable resources and the conservation of soil and water to enhance environmental quality for future generations.  An organic production system is one that is managed in accordance with the Act and regulations in this part to respond to site-specific conditions by integrating cultural, biological, and mechanical practices that foster cycling of resources, promote ecological balance, and conserve biodiversity.  For example, produced chemical pesticides and herbicides are not used in organic farming practices.
• Hydroponic growing is a growing method that uses nutrient rich solutions and alternative means of physical support to grow plants without soil.  Often times, people confuse hydroponic growing with organic as they envision a completely aseptic environment in a greenhouse that would not need the aid of pesticides.  Yes, if hydroponic growers use the aid of a greenhouse they can more easily grow plants without the aid of pesticides given the highly controlled environment.  However, hydroponic growers are permitted to use pesticides, fertilizers, mineral salts and other inputs that would prevent the grower to claim their product as certified organic.  

So, the question becomes...which growing practice best?  I often break my students into small groups and ask them which of the following foods/situations is best....I am met with each group defining the term "best" differently and coming to a variety of conclusions.  And rightly so!  Each of us makes choices in our lives based on what we feel is best.  The real question becomes, what are your priorities?  Is your family strapped for cash and is cost the primary factor in food choice?  Are you a chef who is interested in taste and presentation?  Are you someone battling disease and your focus is on residues and possible contaminants?  Each of us needs to step back and determine what we want out of our food. 

I can weigh in with my thoughts based solely based on the priorities listed below.  Keep in mind these are my personal opinions...and as such they are not Gospel truth with all produce or in all circumstances. 

COST - If cost is your focus and you want to have the most fresh fruits and vegetables for your dollar, generally, modern agriculture produces a safe foodstuff at a reasonable price.

TASTE - Well, what you prefer as a flavor depends on your palate!  John O'Neil, produce purchaser for the Patina Restaurant Group believes that the hydroponic vegetables are lacking flavor.  While one consumer stated, "Hydroponics have a wonderful flirting mild flavor, unlike the crass overpowering aftertaste of common veggies inoculated with dirt and creepy crawlers." It also depends on the produce consumed and the conditions in which it was grown, stored and prepared.

ENVIRONMENTAL IMPACT - Organic farming has a focus of sustainable agriculture leaving little/no chemical residue on the land.  As such, it has gotten the most press for its environmental impact.  When looking at hydroponic farming, it allows us to preserve precious water.  Yes, hydroponics grow plants in water...but, in a very controlled environment.  Thus, hydroponic growers can easily recycle the water not absorbed and it can be reused providing a significantly lower water requirement per plant.  Depending on your environmental priorities as an individual, the two options listed here would be a good choice if you are concerned about mother earth.

FOOD SAFETY - Because of the practice of using manure as a fertilizer in organic growing and modern agriculture, hydroponic growing would be the safest way to avoid bugs like E Coli and Salmonella. 

NUTRITION - According to a met-analysis of the evidence comparing organic and traditionally grown products, vitamin C tends to be a little higher but protein tends to be lower when comparing organically grown produce to traditional growing practices.  According to a recent article in the Journal of Agricultural Food Chemistry, when looking at a variety of antioxidants, organically grown produce tends to have a greater concentration compared to produce farmed with traditional practices.  Ultimately, the growing conditions themselves have the largest impact on the product.  Nutrient content of the soil or solutions applied to the plants, light exposure, temperature, moisture in the air and more can significantly impact individual nutrients in measurable ways.

HEALTH - Because of the nature of research, there is little research documenting human health in response to consuming foods primarily from one of the above methods.  Unfortunately, not enough is known long term for me to make any recommendations. 


I do feel very passionately about one choice that takes all of the above into consideration....plant your own garden!  Whether it be your own hydroponic garden or backyard raised bed, you never know what you are missing until you dig in and do it.  Gardening is very rewarding and delicious.  Mmmmmm!

Savannah and Clayton in 2009 with our garden veggies