My rubber hasn't been looking too great of late, and I noticed with increasing concern a white powdery residue on the leaves. I tried removing it with soap and water but nothing came of it. It's not spider mites, but it seems to be getting worse. Any idea what it could be?

Have you been misting it with water? I have very hard water, and when I mist my plants with it they turn white just like that. I now use distilled water. I cleaned off the powdery stuff with some water mixed with a bit of vinegar. Once they are clean, I only use the distilled water on them.

I agree. The only other thing it could be is powdery mildew, but that should wash off.

Thanks for the replies. I don't mist it anymore but I used to. Let me try the distilled water and vinegar thing.

Let us know if it helps. I hope that was the problem. Hard water beats the bad stuff!

I know this thread is old but I have a rubber plant that looks very similar to the one in the pictures, it's not been misted and I think it might be some sort of fungus? Was this resolved?
Thank you!

@ega - Have you tried wiping the leaves with a solution of mild soap and water? Can you post a photo of your plant?