Pongamia trees grow where citrus once flourished, offering renewable energy and plant-based protein

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An ancient tree from India is now growing in Florida’s citrus orchards, and it could help provide renewable energy for the country.

As large parts of the Sunshine State’s famous citrus industry have nearly dried up over the past two decades due to two deadly diseases, citrus greening and canker, some growers have turned to the Pongamia tree, a climate-resistant tree with the potential to produce plant proteins and sustainable biofuel.

For years, pongamia has been used as shade trees, producing legumes – small brown beans – that are so bitter that wild pigs won’t eat them.

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But unlike the orange and grapefruit trees that have long occupied these rural Florida groves northwest of West Palm Beach, pongamia trees don’t require much attention.

Pongamia trees also do not require fertilizers or pesticides. They thrive in dry or rainy conditions. They do not require teams of workers to pick the beans. All a machine does is shake the young beans from the branches when they are ready to be harvested.

San Francisco-based Terviva, founded by Navin Sikka in 2010, uses its patented process to remove the biocides that cause the bitter taste, making the grain suitable for food production.

“Florida presents a rare opportunity for both Terveva and former citrus growers. The historic decline of the citrus industry has left growers without a crop that can be grown profitably on hundreds of thousands of acres, and a highly scalable alternative is needed as soon as possible,” Sika told The Associated Press. “Pongamia is the ideal choice.”

What is a pongamia tree?

Pongamia is a wild tree native to India, Southeast Asia and Australia.

Legumes are now used to produce a number of products, including Panova cooking oil, Kona protein bars, and protein flour.

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The legumes also produce an oil that can be used as a biofuel, largely for aviation, leaving a very low carbon footprint, said Ron Edwards, chairman of Terveva and a longtime Florida citrus grower.

Turning a wild tree into a home tree was not easy, Edwards said.

“There are no books to read on this subject either, because no one else has done it before,” he said.

Bees and other pollinators feed on the flowers of the pongamia tree, supporting local biodiversity, Edwards said. One acre of trees can provide the same amount of oil as four acres of soybeans, he added.

What remains after the oil is removed from the Pongamia beans is “a high-quality protein that can be used as a substitute in breads, smoothies and all sorts of other plant-based protein products,” Edwards said. “There’s a lot of potential for the food industry, the oil and petroleum industry.”

Why Florida?

“We know that pongamia beans grow well in Florida, and the end markets for pongamia oil and protein—biofuel, feed and food ingredients—are enormous,” Sika said. “So farmers can now lower their costs and align more closely with the latest sustainable farming practices.”

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At a nursery near Fort Pierce, workers specializing in Pongamia grafting techniques attach a portion of the mother tree to the Pongamia rootstock, ensuring that the mother tree’s genes and desirable characteristics continue in all Terveva trees.

Pongamia vs Citrus

Citrus remained the main crop in Florida for years until diseases struck starting in the 1990s with the emergence of citrus canker and then greening.

Bacterial canker disease in citrus is harmless to humans, but it causes cankers in the fruit, stems and leaves. Ultimately, it makes the trees unproductive.

Citrus greening disease, also known as huanglongbing, causes trees to slowly die and the fruit to deteriorate, according to the U.S. Department of Agriculture. The disease has spread throughout Florida since 2005, destroying countless orchards and reducing citrus production by 75 percent. The disease has spread to Louisiana, Texas and California.

Hurricane Ian caused an estimated $1.8 billion in damage to Florida agriculture in September 2023, hitting the citrus industry at the start of its growing season.

Disease and climate issues have also affected most of the world’s citrus-producing countries. For example, this year’s harvest in Brazil—the world’s largest exporter of orange juice—is expected to be the worst in 36 years due to flooding and drought, according to Fundecitrus, an organization of citrus growers in the state of São Paulo.

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But company officials said climate and disease had little impact on the pongamia trees.

“It’s a very tough tree, and it’s been tested in the forest,” Edwards said. “It takes a lot of abuse with very little care.”

Pongamia plants also grow well in Hawaii, where they now thrive on land formerly used for sugarcane cultivation.

What do citrus growers say?

John Olson, owner of Circle O Ranch, west of Fort Pierce, replaced his grapefruit groves with 215 acres (87.01 ha) of pongamia trees.

“We went through all the ups and downs in citrus farming, and eventually, because of the deforestation, citrus production stopped,” Olson said. “The citrus industry in Florida mostly died.”

Although the grapefruit orchard was modest, it was common for an orchard of that size to be profitable in the 1980s and 1990s, Olson said.

Edwards said farmers used different types of pesticides to kill the insect that was spreading the disease. Eventually, the cost of maintaining the citrus trees became prohibitive.

Then he decided to take a different path.

“What attracted me to pongamia was the fact that it could reuse fallow land that had been planted with citrus and was now dormant,” he said. “From an environmental point of view, it’s very attractive because it could replace some of the vegetable oils and proteins that are now produced from things like palm oil, which is a much more environmentally harmful crop.”

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What about biofuel?

In December 2023, Terviva signed an agreement with Mitsubishi Corporation to provide biofuel feedstock that can be converted into biodiesel or renewable diesel.

“Our partnership with Mitsubishi has started off great,” said Sika, noting that the company is closely coordinating with Mitsubishi on tree planting, product development and sales. “Terviva’s progress has been accelerated by Mitsubishi’s expertise and global leadership in all aspects of Terviva’s business.”

What food products does Pongamia produce?

The research is still ongoing, but Edwards said they’ve made pretty good graham crackers with cooking oil and other plant-based protein products, including flour and protein bars.

Bongamia offers an alternative to soy protein and yellow peas “if you don’t want the protein to come from meat,” he says.

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