Grant Helps Growers Better Manage Nutrients 

By Brandon Schrand
WSU College of Agricultural, Human and Natural Resource Sciences

Since the 1960s, American grape growers have followed a set of nutrient management guidelines that often entail more guesswork than precise strategies. An industry-driven project called “High-Resolution Vineyard Nutrient Management” seeks to change that. Led by Washington State University’s Dr. Markus Keller, it was one of the projects funded this year by the USDA National Institute of Food and Agriculture’s highly competitive Specialty Crop Research Initiative (SCRI). It officially launches today (September 30).

Historically, growers have relied on a one-size-fits-all method of managing nutrients, delivering the same amount of fertilizer to an entire vineyard block. That’s because assessing the nutrient status of individual plants or even sections of a vineyard by conventional methods is impractical and costly. “While much of the crop receives the right amount of fertilizer, sections or individual plants may receive too much or too little,” Markus says. “We want to reassess the way we approach nutrient management.”

By using remote sensors and other technologies, Markus and a team of scientists from across the country hope to identify hitherto hard-to-detect nutrient surpluses or deficiencies (particularly nitrogen, potassium and phosphorous) in a timely manner, so that growers can make more nimble management decisions. “Right now, leaf analysis can take up to a couple of weeks,” he says. “By the time the grower gets the results, it’s often too late to correct any inadequacies.” Nutrient-wise, soil can vary tremendously across the block, and plants are very selective about what they take from it, he adds.

Conventional methods of managing vineyard nutrition are still important for grape growers; this new research seeks to supplement rather than replace them. The more resources and data growers have, the more efficient and productive their vineyards become. That benefits more than just growers.

“This kind of approach could go a long way in helping the environment, too, by reducing the amount of fertilizers being used, and by applying them at the right time in the right place,” Markus says. Plus, a reduction in inputs could be passed along, not only in end-price but also fruit and wine quality, benefitting consumers, too.

It’s important to note, he says, “there’s a strong Extension component to this project. In addition to providing training to growers around the country, we want to develop apps and other decision-support tools to [help them] form and augment their nutrient-management plans.” The project spans all viticulture and covers 97% of U.S. grape production regions. “We want all grape growers to benefit from this research,” Markus says.

The project is a collaborative effort between WSU and Cornell, UC Davis, Oregon State, Rochester Institute of Technology, Virginia Tech and USDA-ARS. The total SCRI grant is $4.75 million, of which the first $1 million has been approved. Subsequent installments of the grant will be contingent on the project’s progress. Financial support also comes from the Washington State Wine Commission’s Research Program and the Washington State Concord Grape Research Council.

NGRA originally conceived of the project. “[It] has been industry-driven from its earliest conception, and continues to be,” Markus says. “Given the prestige of all the institutions involved, it is a great honor to have been asked by NGRA to lead such an exciting and dynamic project,” Markus says.

Read the original article, published in the WSU Insider on September 25.