I have 3 Mandeville's that have white patches(sort of fluffy) on them. I cut them back to about 18 inches high, set them in bath tub and sprayed them with water and wiped off all the white that was possible, then I sprayed them with Garden Safe Insecticidal Soap. Within a week the white spots are back and getting bigger. These plants are being kept in the house through the winter since I live in zone 6. Any advice will be greatly appreciated. Thank You
Mandevilla has a milky sap that is similar to Elmer's glue. It may just be "bleeding". I really can't tell much from your pictures because they are out of focus. I would suggest that next time you place a piece of paper directly behind your subject to help your camera focus on the right area and use your macro setting (if your camera has one) which is usually labeled with the icon below:
I will try to get a better picture. I don't know if these pictures will be any better. There seems to be stringy cob webs when I try to pull the white stuff off the plant. I appreciate any information that you can give me.
Mealy bugs
Much better pics and, yes, that's mealybug. You might need something slightly stronger than soap. Do you have any systemic insecticides?
neem oil work on those?
nope.
Imidacloprid or Spinosad do.
