Sooty mold, which forms on “honey dew” (an insect byproduct) is a fungal infection on plants.
The most recent insect culprits behind the latest stint in Florida is an infiltration of Rugnose Whiteflies, Croton Scale, and Nesting Whiteflies.
Controlling the mold on plants is handled the same way as handling house mold. Eliminating the cause eliminates the mold. In a house, that means eliminating water intrusion. In the garden it means eliminating the pest intrusion.
Pesticides are a last resort. The first thing to do is to cut back foliage where you can. High pressure spray, (or spraying with soap or oil treated water) can help eliminate the bugs that cause the mold. Green agricultural centers may teach ways to encourage Ladybugs or Lacewings or may even provide sources who sell these beneficial insects to help you curtail the insect problem causing your mold problem.
If you’re in California, you might want to give us a call and see about getting an assessment from Byebyemold.