2026–2027 Florida Citrus Production Guide: Citrus Scab

Application Timing Recommendations

• Do NOT use a strobilurin fungicide (FRAC MOA 11) for two applications in a row.
• Resistance is a risk for this fungal disease.
• For a heavy infection during the previous season, three applications are needed.

1. At ¼ spring flush expansion:
• Enable 2F, Gem, Headline, or Quadris are the best choices at this timing.
2. At petal fall:
• If you chose a strobilurin (FRAC MOA 11) for the first application, do not use here.
3. Three weeks following the second application:
• Copper fungicides, Gem, Headline, or Quadris.

• If there is a small amount of disease the previous season, the first application can be omitted.
• If scab severity is high, do not use copper alone for the third application.

DO NOT APPLY GEM, HEADLINE, OR QUADRIS IN NURSERIES. Application of these fungicides in nurseries can result in selection of resistant strains, which are then distributed on nursery stock to groves.

Recommended Chemical Controls

READ THE LABEL.

See Table 1.

Rates for pesticides are given as the maximum amount required to treat mature citrus trees unless otherwise noted. To treat smaller trees with commercial application equipment including handguns, mix the per-acre rate for mature trees in 125 gal of water. Calibrate and arrange nozzles to deliver thorough distribution, and treat as many acres as this volume of spray allows.