EARTH grows only a fraction of that total, shipping about half a million boxes of bananas to Whole Foods each year.
But officials say that the green measures pioneered at the school are steadily being adopted by other growers.
For example, standard banana plantations tie plastic bags around budding bunches to protect the fruit from scarring and to keep out unwanted pests.
Discarded, pesticide-covered bags often wind up clogging rivers and watersheds, so EARTH began a plastic-bag recycling program. (Watch a video of Edward Norton describing the environmental impact of plastic bags.)
"When we started [recycling bags] people laughed at us and said it couldn't be done," said Panfilo Tabora, an EARTH professor who heads an organic teaching farm on campus.
Today almost all banana growers in Costa Rica have adopted bag-recycling programs. The Dole Food Company, one of the largest banana producers in the country, annually recycles about 1,900 tons of plastic.
Dole also recently signed an agreement with the Costa Rican government to produce a carbon-neutral supply chain for bananas and pineapples grown there.
"We are determined to take the lead in sustainable and environmentally friendly [fruit] production and distribution methods," said Marty Ordman, vice president of marketing for Dole based in Westlake Village, California.
Road to Organic
The school is now working on producing completely organic bananas in the near future.
But a major challenge is black sigatoka, an airborne fungus that shrinks the fruit and can eventually kill the plant.
For now only powerful fungicides can fully combat the disease.
The worm-like nematode Radopholus similes is another serious problem for banana growers. The organism attacks the roots of banana plants and causes them to suffer from malnutrition.
So EARTH's organic farmers developed fertilizers that include "effective microorganisms"—benign bacteria, yeasts, and fungi that crowd out nematodes and minimize disease.
"Something like 40 percent of banana-growing areas in Central and South America and even Asia are now using the techniques we have developed here," EARTH's Tabora said.
In addition to the environmental consequences, using pesticides and herbicides is a burden to plantation laborers, who reportedly suffer from sterility, cancers, and other conditions after years of exposure.
Michael Besancon is president of the Southern Pacific division of Whole Foods Market based in Sherman Oaks, California.
He said the overall goal for the banana-producing business should be achieving sustainability, which means not just reducing chemical use but also providing good wages and working conditions for the farmers.
"If you reduce the amount of pesticides that go into [the watershed] then you have done a really good thing," Besancon said.
"But as we have evolved our thinking as an industry, the issue of sustainability has become the definition—whether or not something is sustainable from an economic and social as well as an environmental standpoint."
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