The vineyard at NMSU’s Sustainable Agriculture Science Center at Alcalde has been used for a recent study of organic alternatives to petroleum-based fertilizers. The researchers were interested in learning if it would be cost-effective for producers to use leguminous cover crops and locally generated compost to supply necessary nutrients.

The research was conducted by Ron Walser, now-retired fruit specialist at the Alcalde science center; Robert Flynn, associate professor in Extension Plant Sciences and Extension agronomist at the Artesia science center; April Ulery, professor in the Department of Plant and Environmental Sciences; Steve Guldan, agronomy professor in PES and superintendent of the Alcalde science center; and Milagra Weiss, then a student in PES. They presented their findings, based on data gathered between 2002 and 2006, in a paper titled “Cover Crops and Compost Amendments for Organic Grape Production.”

Among the conclusions of the study, the researchers found that using the combination of New Zealand white clover as a cover crop and an alfalfa and horse manure compost “will provide adequate mineral nutrition and increase soil organic matter as well as provide for ecological gains.”

At NMSU’s Agricultural Science Center at Farmington, a study of both wine grapes and table grapes is winding down after five growing seasons of evaluation. The research is being conducted by Kevin Lombard, who is a Farmington-based assistant professor and horticulture specialist in the Department of Plant and Environmental Sciences, and Maier.

The project includes a study of both red and white wine grapes on vines planted in 2007 and a trial of rootstock varieties planted in 2008, as well as temperature monitoring of San Juan County vineyards. The research all focuses on the challenges of raising grapes in the high-altitude environment of the Four Corners area.

The differential effects of a hard spring freeze in 2010 on the vines and on grape production were well-documented in this study. Freeze damage, as measured in May, was lowest for Malbec among the reds and Vidal Blanc among the whites. In terms of post-freeze recovery and productivity, Baco Noir, Kozma and Leon Millot fared best among the reds, while Chardonel, Seyval Blanc, Siegfried, Traminette, Valvin Muscat and Vidal Blanc had the highest yields among the whites.

Freezing temperatures continued to be a problem for the Farmington vineyard in 2011. “We had cold winter temperatures in January and February,” Lombard said. “Then a killing spring frost occurred May 2 and 3, at the time of bud break, which is probably what sealed the deal on susceptible grape cultivars, including Malbec and Zinfandel.”

Many of the vines that have been performing marginally will be replaced by new entries in 2012, according to Lombard. “They will be used for ongoing evaluations of winter cold tolerance, spring dormancy break, adaptability to high pH soils and yield,” he said. “Simply growing grapes is not enough. Evaluating market potential is also important and factors prominently into the evaluations.”

To learn more about all aspects of New Mexico viticulture and NMSU support for the wine industry, go to http://aces.nmsu.edu/ces/viticulture/

For NMSU publications about viticulture and wine, use the search tool at http://aces.nmsu.edu/pubs/