See what the scientific research from UF/IAS says about combating fruit drop in citrus the Florida citrus industry.
“Fruit drop has become one of the biggest challenges for Florida citrus growers, especially in groves hit hard by HLB,” shared a Citrus Industry article about the latest research into combating fruit drop in citrus. Disease, hurricanes, and stresses like drought are all contributing to the problem. Florida citrus growers are utilizing plant growth regulators (PGRs) like gibberellic acid (GA, ProGibb LV Plus by Valent BioSciences) and 2,4-D (Citrus Fix by AMVAC), according to the article. See what the science says about reducing citrus fruit drop.
Reducing Fruit Drop in Citrus
According to the article, gibberellic acid (GA) “helps keep the peel and canopy healthier for longer,” and “2,4-D works directly to slow the fruit’s natural ‘drop signal,’” and that “Both also push back against ethylene, the plant hormone that drives premature drop in HLB trees.”
The research included a “two-year field trial on mature Valencia in Polk County” that “tested different approaches,” including:
- “An untreated control
- A single November spray of 2,4-D at the label rate
- Three smaller sprays at 1 ounce per acre spread out September through November
- A tank mix of 2,4-D (3.2 ounces per acre) plus GA (10 ounces per acre)”
Takeaways included:
- “The GA + 2,4-D combination cut fruit drop by about 16% in the first year.
- In the second year — despite Hurricane Milton — trees treated with either 2,4-D alone or the GA + 2,4-D mix lost at least 20% less fruit than untreated trees.
- Treated trees also produced more fruit per canopy size, showing better efficiency even under storm stress.
- Multiple small sprays of 2,4-D did not provide any extra benefit in reducing fruit drop.”
The takeaway for combating fruit drop in citrus was “that one well-timed November spray of 2,4-D along GA works very well in reducing fruit drop. Using these PGRs, especially after hurricanes, can help reduce drop and protect yields in HLB-affected citrus.”
Griffin Fertilizer is committed to helping both growers and ranchers make sound agronomic and economic decisions in order to maximize the health of their grove and pasture. As a full-service custom dry & liquid fertilizer blender and crop protection product distributor, we will continue our mission to further advance Florida agriculture. For questions -or concerns about your farm or pasture, contact us and one of our team will be in touch.