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

An ancient tree from India is now flourishing in Florida orchards where citrus trees once grew. It could provide the country with renewable energy.

As large parts of the Sunshine State’s once-famous citrus industry have all but dried up over the past two decades due to two deadly diseases, citrus greening and citrus canker, some farmers are turning to the pongamia tree, a climate-resilient tree with the potential to produce plant-based protein and a sustainable biofuel.

For many years, pongamia was used as a shade plant for trees. It produced legumes (small brown beans) that were so bitter that wild boars would not eat them.

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

Pongamia trees also don’t need fertilizers or pesticides. They thrive in dry or rainy conditions. And they don’t need teams of workers to pick the beans. A machine simply shakes the small beans off the branches when they’re ready to harvest.

Terviva, a San Francisco company founded in 2010 by Naveen Sikka, then uses its patented process to remove the biopesticides that cause the bitter taste, making the beans suitable for food production.

“Florida presents a rare opportunity for both Terviva and former citrus farmers. The historic decline of the citrus industry has left farmers without a crop that can grow profitably on hundreds of thousands of acres, and a highly scalable replacement needs to emerge very quickly,” Sikka told The Associated Press. “Pongamia is the perfect fit.”

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

The legume is now used for the production of multiple productsincluding Panova cooking oil, Kona protein bars and protein flour.

The legumes also produce oil that can be used as biofuel, particularly for aviation. According to Ron Edwards, chairman of the board of Terviva and a longtime citrus grower in Florida, this has a very low carbon footprint.

Transforming a wild tree into a domesticated tree was not easy, Edwards says.

“There are no books to read about it either, because no one else has ever done it,” he said.

Bees and other pollinators feast on the pongamia flowers, which helps support local biodiversity, Edwards said. An acre of trees can potentially yield the same amount of oil as four acres of soybeans, he added.

What’s left after the oil is removed from the pongamia bean is “a very high-quality protein that can be used as a replacement in baking and smoothies and all sorts of other plant-based protein products,” Edwards said. “There’s a lot of potential for the food industry and the oil and petroleum industry.”

“We know that pongamia grows well in Florida, and the end markets for the oil and protein that come from pongamia beans — biofuel, feed and food ingredients — are huge,” Sikka said. “Farmers can now reduce their costs and better align themselves with the forefront of sustainable agricultural practices.”

At a nursery near Fort Pierce, workers specializing in pongamia grafting techniques attach a section of the mother tree to a pongamia rootstock, ensuring that the genetics and desirable traits of the mother tree are retained in all Terviva trees.

Citrus was the most important crop in Florida for many years until it was struck by a disease in the 1990s that led to citrus canker and later greening.

Citrus cancera bacterial disease, is not harmful to humans, but causes lesions on the fruit, stems and leaves. Eventually it makes the trees unproductive.

Citrus greening, also known as Huanglongbing, slowly kills trees and degrades the fruit, according to the U.S. Department of Agriculture. Greening has spread throughout Florida since 2005, devastating countless orchards and reducing citrus production by 75 percent. The disease has spread to Louisiana, Texas and California.

Hurricane Ian caused approximately $1.8 billion in damages in Florida agriculture in September 2023, hitting the citrus industry at the start of the growing season.

Diseases and climate problems have also affected most of the world’s major citrus producing countries. For example, this year’s harvest In Brazil, the world’s largest exporter of orange juice, the situation will be the worst in 36 years due to flooding and drought, according to a forecast by Fundecitrus, an organization of citrus growers in the state of Sao Paulo.

But climate and disease have little effect on pongamia trees, company officials say.

“It’s just a tough, jungle-tested tree,” Edwards said. “It can take a lot of abuse and it doesn’t need a lot of care.”

Pongamia also grows well in Hawaii, where the plant now thrives on land previously used for sugarcane.

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

“We’ve been through all the ups and downs of citrus and ultimately, because of greening, we stopped producing citrus,” Olson said. “The citrus industry is largely dead in Florida.”

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

Edwards said farmers used a variety of sprays to kill the insect that spread the disease. Eventually, the cost of caring for citrus trees became too risky.

Then he decided to take a different path.

“What attracted me to pongamia was the fact that it can repurpose fallow land that was citrus and is now dormant,” he said. “From an ecological point of view it’s very attractive because it can replace some of the oils and vegetable proteins that are now generated by things like palm oil, which is a much more damaging crop to the environment.”

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

“Our partnership with Mitsubishi is off to a good start,” Sikka said, noting that the company works closely with Mitsubishi on tree planting and product development and sales. “Terviva’s progress has been accelerated thanks to Mitsubishi’s expertise and leadership around the world in all facets of Terviva’s business.”

The research is still ongoing, but Edwards says that in addition to the cooking oil and other plant-based protein products, including flour and protein bars, they’ve also created some really tasty graham crackers.

Pongamia offers an alternative to soy and yellow pea proteins “if you don’t want your protein to come from meat,” he said.