What can I use to spray our Plumaria (Frangipani) plants for rusty looking scale on the back of the leaves?

Question

The leaves turning yellow with dark spots, some curling and falling off. I think the reason for this is excessive rains and humidty in Florida. This is the first time this scale has shown up. Thanks for your time.

Answer 1

This article should help:

https://www.gardeningknowhow.com/ornamental/flowers/plumeria/plumeria-plants-with-rust-fungus.htm