Writer: Jane Moorman, 505-249-0527, firstname.lastname@example.org
LOS LUNAS - Which irrigation technique is more efficient for vegetable gardening - furrow or drip? And which will have a better yield and profit margin?
These are the questions being studied at New Mexico State University's Agricultural Science Center in Los Lunas this summer, under the direction of Ron Walser, urban small farm specialist.
"We are planting two gardens, each a third of an acre, with identical rows of vegetables. The only difference will be how we water the plants," he said Thursday, April 19, as Valencia County Master Gardeners and interested residents helped install the irrigation tapes in the field. "We will meter the water use in each garden, record the labor required by each system and ultimately determine the difference in yield."
Walser said the project will include selling the produce at farmers' markets to determine the profitability of the two systems.
Before planting, the fields were prepared for traditional furrow irrigation, and for drip irrigation, which involved placing irrigation tape the length of the row in three configurations.
"For some of the vegetable plants the irrigation tape is uncovered, but for the other plants it is covered with either black or silver plastic," Walser said. "The plastic is mainly for weed control, but also helps keep the produce, such as strawberries, off of the ground. But it also helps prevent evaporation of the water from the soil."
Walser and the research farm staff demonstrated how the irrigation tape and plastic are mechanically installed behind a tractor. A combination of plow discs and wheels placed the irrigation tape under the plastic and tilled dirt along the edge to hold the plastic down.
"When we plant, we will cut holes in the plastic at one-foot intervals where the emitter holes are in the tape," Walser said. "We will be planting a wide array of vegetables and several varieties of each one."
Many of the vegetable plants have been started in the greenhouse, but some, such as green beans, peas, radishes, carrots and spinach, will be from seeds planted directly in the row. The list of produce includes cantaloupe, green chile, jalapeņo peppers, bell peppers, tomatoes, cucumbers, artichoke, Swiss chard, beets, lettuce, squash, okra and cole crops such as cabbage that enjoy the cool season and are somewhat cold tolerant. Included in the planting will be a variety of herbs and cut flowers.
The cost for the irrigation system, which Walser says will serve two growing seasons, is approximately $120 for 5,000 feet of the irrigation tape and $100 for a 3,000-foot roll of plastic. In addition, a PVC pipe system was installed at the head of each row to bring the water to the field. This system includes filters, volume meter, fertilizer injection system and pressure control that will maintain the water at 10 pounds of pressure.
"Water pressure any higher than 15 pounds will cause the irrigation tapes to balloon up and split open," Walser said.
The field test is among the various projects Walser is starting at the Los Lunas research farm to introduce new farming techniques for small acreage in the Middle Rio Grande Valley. In addition, an orchard with nearly 100 varieties of fruits has been planted.
"By our field day on Aug. 15, we should have a fully producing commercial garden," Walser said. "The orchard will not be producing fruit until next year."
The research project is part of NMSU's continuing outreach efforts to help educate and improve the lives of people in New Mexico.
© 2013 New Mexico State University Board of Regents
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