Hydroponic lettuce project leaves the dirt behind

lettuce medium

Northwest agriculture students have been growing hydroponic lettuce and
endive in a University greenhouse in order to determine the impact of organic
compost. Hydroponics is a method of growing plants in a nutrient solution
so that no soil is required.

So who says farmers need dirt? Certainly not a group of agriculture students at Northwest who are currently wrapping up an experiment using hydroponically grown lettuce.

Hydroponics is a method of growing plants using mineral nutrient solutions instead of soil. When the required nutrients are introduced into a plant's water supply artificially, soil is no longer required for the plants to thrive.

Rego Jones, instructor of horticulture, said the primary purpose for cultivating a half-dozen varieties of lettuce and endive in greenhouse No. 5 on the Northwest campus is to study the effects of an organic plant compost, which was introduced into a portion of the study plot.

The “plot,” however, is actually a series of long plastic pipes with holes drilled in them. Individual plants, sprouted from seeds this fall, have been inserted in the holes, their roots covered with small plastic cones.

A nutrient solution, in the form of clear liquid, is pumped repeatedly through the pipes, which incline slightly and allow the solution to flow back out into holding tanks. Artificial lamps provide extra light at the end of short fall days, and greenhouse heaters and refracted sunlight keep the temperature at around 40 degrees.

The result is something like June in November. Full, leafy plants explode from the pipes in an array of shades and textures that would catch the eye of even the pickiest shopper at any farmer’s market.

Jones said the solution contains basic nutrients like nitrogen, potassium and phosphorus along with a number of secondary and trace elements. He noted that the plants receiving the compost-laced solution have a different coloration that probably indicates increased nutritional value.

Students from greenhouse crop production and advanced crop production classes will soon harvest the plants so that they can be fully analyzed and the results of the experiment recorded.

“What we really want to see is if the organic compost makes a difference,” said Jones, adding that a secondary aim is to expose students to the hydroponic techniques themselves.

“This certainly has commercial applications,” he said of growing plants in a soilless environment. “There are all the issues surrounding E. coli and so forth, but here you have roots that are not exposed to any kind of contaminant. There are no pests, no rain and no dust.”

For more information, please contact:

Anthony Brown,
News Bureau Manager
E-Mail: abrown@nwmissouri.edu
Phone (660) 562-1704
Fax (660) 562-1900

Northwest Missouri State University
219 Administration Building,
800 University Drive
Maryville, MO 64468

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