Hi, need advice on controlling a scale infestation on a Rhapis Palm. The palm lives in a large pot on an apartment balcony in full shade. I have been treating the infestation by spraying neem oil once a week for 8 weeks and removing the scale by hand, however the problem is not getting any better. The scale is covered in a white powdery substance that the ants love. Please any suggestions on how to tackle this? and ideal neem oil spray dilution rate. thank you in advance. Rachel