Study recommends strategies for improved management of fresh market spinach

Sep 16, 2013

Throughout California's fertile central coast region, fresh spinach is a high-production, high-value crop. Spinach can be finicky, requiring sufficient nitrogen fertilizer and irrigation to ensure ideal growth, and to meet industry quality standards such as its defining deep green color. These production practices—combined with a shallow root system and the crop's intensive production cycle—can increase the potential of detrimental nitrate leaching. Recent water quality monitoring in the region has found widespread incidences of NO3 levels that exceed the Federal Drinking Water standard. As a result, growers have come under increasing pressure to improve crop nutrient use efficiency (NUE), and thereby minimize NO3 losses from production fields. In an effort to inform future spinach production practices, scientists Aaron Heinrich, Richard Smith, and Michael Cahn evaluated spinach nutrient uptake and water use in the Salinas and San Juan Valleys of California.

The team explained that spinach producers can improve nitrogen use efficiency by applying fertilizer at the optimal time and rate to match crop nitrogen uptake, but that data needed to make these critical fertilizer decisions was not available prior to their study. "No studies had evaluated high-density planting of clipped or bunched spinach grown on 80-inch beds," said lead author Aaron Heinrich. "Our study was specifically designed to provide data on the nitrogen uptake characteristics of spinach and to evaluate ways to improve nitrogen fertilizer management."

Heinrich, Smith, and Cahn evaluated grower fertilizer programs, and measured spinach nitrogen uptake over an entire production season with a range of , climatic conditions, and cropping histories. They also conducted four replicated fertilizer trials of first—and second-cropped fields.

"Over the growing season, NO3 levels in the soil can build up due to a combination of unused fertilizer and mineralization of and soil organic matter," the team reported "Our evaluations showed that soil NO3 testing can be used to improve the nutrient use efficiency of spinach. We found that soil testing would be most effective in spinach production at two critical points: at-planting, and before the midseason fertilizer application when nitrogen use by spinach greatly increases." The comprehensive report, including additional implications for management of fresh market spinach, can be found in the June 2013 issue of HortTechnology.

Explore further: Heavy rains can strip away mobile soil nutrients

More information: The complete study and abstract are available on the ASHS HortTechnology electronic journal web site: horttech.ashspublications.org/content/23/3/325.abstract

Provided by American Society for Horticultural Science

not rated yet
add to favorites email to friend print save as pdf

Related Stories

Heavy rains can strip away mobile soil nutrients

Jun 18, 2013

(Phys.org) —Heavy spring rains in portions of the state have probably increased yield potentials but may also be increasing nutrient losses of nitrogen, sulfur and chloride. In addition, water-logged soils and cool temperatures ...

Nitrogen applied

Oct 01, 2008

Combating soil erosion is a primary concern for agricultural producers in the United States, and many have incorporated conservation tillage systems in their effort to maintain a profitable crop output.

Benefits of Bt corn go beyond rootworm resistance

Feb 06, 2013

Engineered to produce the bacterial toxin, Bt, "Bt corn" resists attack by corn rootworm, a pest that feeds on roots and can cause annual losses of up to $1 billion. But besides merely protecting against these losses, the ...

Battling climate change with tried-and-true methods

Mar 29, 2013

For decades, farmers in Montana and the Dakotas have produced impressive yields of barley and wheat. But that bounty has come at a cost. Tilling the soil in the region's crop-fallow production systems has ...

Recommended for you

More, bigger wildfires burning western US, study shows

8 hours ago

Wildfires across the western United States have been getting bigger and more frequent over the last 30 years – a trend that could continue as climate change causes temperatures to rise and drought to become ...

User comments : 0

More news stories

There's something ancient in the icebox

Glaciers are commonly thought to work like a belt sander. As they move over the land they scrape off everything—vegetation, soil, and even the top layer of bedrock. So scientists were greatly surprised ...

Clean air: Fewer sources for self-cleaning

Up to now, HONO, also known as nitrous acid, was considered one of the most important sources of hydroxyl radicals (OH), which are regarded as the detergent of the atmosphere, allowing the air to clean itself. ...

China says massive area of its soil polluted

A huge area of China's soil covering more than twice the size of Spain is estimated to be polluted, the government said Thursday, announcing findings of a survey previously kept secret.

Hackathon team's GoogolPlex gives Siri extra powers

(Phys.org) —Four freshmen at the University of Pennsylvania have taken Apple's personal assistant Siri to behave as a graduate-level executive assistant which, when asked, is capable of adjusting the temperature ...

Better thermal-imaging lens from waste sulfur

Sulfur left over from refining fossil fuels can be transformed into cheap, lightweight, plastic lenses for infrared devices, including night-vision goggles, a University of Arizona-led international team ...