Roger Ruiz is growing bananas in a more sustainable way, starting with the 800-acre plantation at EARTH agricultural university on Costa Rica’s Atlantic coast.

Surrounded by multinationals, EARTH’s head of commercial operations said he and his team have made significant progress in the last few years.

“Our farm is like a live lab where our 400 students can research new practices and techniques to grow in the tropics,” said Ruiz.

The non-profit university expects to export more than 700,000 boxes of bananas to the U.S. this year through ports in Houston and Philadelphia, he said. Some 80% goes to Austin, Texas-based Whole Foods Market, which pays a premium for EARTH bananas.

The relationship with Whole Foods began in 1983 with one container a week, he said, and has grown to 12 a week. He estimates EARTH now supplies 75% of Whole Foods stores, and hopes to be able to supply all its stores within four years. Chiquita Brands International Inc. buys another one or two containers a week depending on production, he said.

Though the rains have come and the weather looks good for bananas until the end of the year, Ruiz said this year has been the driest in a decade in Costa Rica, and one of the three driest in the last 200 years.

“It’s incredible that many producers are considering installing expensive irrigation systems in humid Costa Rica,” he said.

Bananas in the tropics are constantly threatened by black sigatoka, a fungal disease that leaves dark spots on the leaves and can cut a tree’s fruit production in half.

“Traditional control of black sigatoka involves a huge chemical load on banana farms and represents about 25% of in-farm production costs,” said Ruiz.

To combat the disease, EARTH professors created a mixture of mico-organisms called EM. It has proven effective at the university’s farm and in Chiquita plantations since 2007 without any reduction in yield, Ruiz said.

Trees grow along the river banks and ground cover grows in the farm’s drainage ditches to reduce erosion and prevent water contamination, Ruiz said. An innovative water filtration system allows packing plant workers to reuse 30% of their water.