Frangipani rust is a fungus which survives on the underside of frangipani leaves.
It first appears as a few very small gold spots on the underside of old frangipani leaves but the spores quickly multiple and turn into hundreds of gold spots. The spots look similar to rust spots on metal so the name has stuck. When disturbed, the spores take a powdery dust form and easily float through the air to infect nearby frangipanis.
Because frangipani rust multiplies rapidly and is easily transferred to other frangipanis,
it’s important to treat the frangipani rust as early as possible and as often as possible to ensure the rust does not spread.