CITRA, Fla. — Once standing at 18 feet tall and requiring ladders for harvest – the citrus trees are now barely half that height and struggle to survive in the grip of disease.
These citrus trees, located at The Orange Shop in Citra, tell a story of decline.
“Greening started (a dozen) years ago, and it’s devastated the trees,” said Ronald Rorick, a farmer and worker at The Orange Shop. “They just aren’t what they used to be, and it’s heartbreaking to see.”
Research coordinator for the Citrus Research and Development Foundation Brandon Page said Citrus greening, or Huanglongbing, is the most significant challenge facing Florida’s citrus industry. It’s a bacterial disease spread by the Asian citrus psyllid, a small but highly mobile insect that transmits the infection as it feeds on citrus trees. The disease damages the trees’ vascular systems, cutting off their nutrient supply and slowly leading to their decline.
“The roots start to deteriorate before you even see symptoms above ground,” Page said. “Once the vascular system is compromised, the tree can’t balance its canopy and root system.”
A cure for Citrus Greening remains elusive. However, recent advancements offer new tools to manage its effects. Researchers at UF’s Institute of Food and Agricultural Sciences (UF/IFAS) are working on a few innovative solutions to help farmers combat the disease and extend the lives of their trees.
One promising approach involves the use of plant hormones like gibberellic acid and synthetic auxins.
“These hormones help improve overall tree health and reduce pre-harvest fruit drop,” Page said. “They’re not a silver bullet, but they’ve shown measurable benefits.”
Pre-harvest fruit drops refer to fruit that looks healthy on the citrus tree, but fall off the trees and to the ground before it’s ready to be picked for harvest.
Another possible solution is trunk injection therapy, a labor-intensive process that involves injecting antimicrobials directly into the tree’s vascular system. While the method requires treating each tree individually, it has proven effective.
“Trunk injections improve tree health, fruit quality, and yield,” Page said. “It’s becoming a standard practice for many growers.”
Additionally, researchers are working on long-term solutions, such as breeding new citrus varieties that are resistant or tolerant to the disease. However, progress is slow due to the nature of citrus as a perennial crop.
“With citrus, it can take years—sometimes decades—to evaluate the results of a new therapy or breeding program,” Page explained. “That’s a big challenge compared to row crops like corn or soybeans, where you can gather data in a single growing season.”
For many farmers, this fruit loss represents not just a reduction in crop yield but also a blow to fruit quality. “Before greening, it was common to see sugar content, or pounds solids, in the sixes and sevens. Now, it’s closer to four statewide,” Page said.
The challenges are forcing some farmers to abandon citrus altogether. In many areas of North Central Florida, former groves have been cleared to make way for housing developments, spurred by high land values.
“If growers can’t produce a viable crop, selling their land to developers becomes an easy choice,” said Ed Etxeberria, an emeritus professor at UF.
While researchers and farmers continue to fight for the future of Florida’s citrus industry, the road ahead remains uncertain. For growers like Rorick, the battle against greening is personal.
“It’s tough to keep going when you see the trees struggling like this,” he said. “But citrus is part of Florida’s history. We have to keep trying.”
“I am optimistic about it,” Page said, referring to the future of Florida’s citrus industry. “We do have some things on the way in the world of plant breeding and creating trees that are highly tolerant or maybe even truly resistant to the disease.”