See recommendations and tips on timing for Florida citrus growers utilizing oxytetracycline injections to combat citrus greening.
Many Florida citrus growers are utilizing oxytetracycline injections in their citrus groves to combat the effects of citrus greening, also called HLB, and to help their trees recover from the effects of the disease. In March 2025, several UF/IFAS researchers issued “Suggested Use Pattern of Injectable Antimicrobials for Huanglongbing (HLB) Management,” to help Florida citrus growers with the ways and means of injections. The document does read that “This is not an official University of Florida recommendation,” as UF/IFAS likely does not have enough years of data for recommendations on injecting oxytetracycline, but the document was authored by associate professors in either Horticulture or Plant Pathology, U. Albrecht, O. Batuman, and M.M. Dewdney. See the recommendations below.
Recommendations on Timing Oxytetracycline Injections
The document shares an Antibacterial Product Application Schedule. It advises that “The application schedule should be adjusted based on expected harvest time and flowering…Only one application per year is allowed for bearing trees, but non-bearing trees can be injected twice annually with a 4-month interval.” The most desirable months to administer oxytetracycline injections by citrus type include:
- For Early Season Varieties (Ex. Hamlin, Navel, Fallglo): March, April, and May; June is a possibility, but less desirable.
- For Mid Season Varieties (Ex. Murcott, Pineapple, Midsweet): March, April, May, and June; July is a possibility, but less desirable.
- For Late Season Varieties (Ex. Valencia): March, April, May, June, and July; August is a possibility, but less desirable.
- For Grapefruit (Ex. Ray Ruby, Flame, Ruby Red): March, April, and May; June is a possibility, but less desirable.
- The documents advises that “The latest possible injection application should be determined based on the 180-day PHI from the expected harvest date.”
The document also advises that the labels for whatever is being applied supersedes everything else because ‘THE LABEL IS THE LAW! Refer to the label for additional information. This guide does not supersede the label.”
Be on the lookout for our next blog that looks at application recommendations.
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.