I brought my plumaria plant indoors in early October in NJ, zone 7, when the night temperatures were falling below 40. It started blooming beautifully last week and there are still many buds. However now the flowers have fallen off and many leaves are turning rusty and falling off. I sprayed the whole plant and soil with Neem Oil but I don't know if it is helping. What else can I do?

Plumeria rusts are fairly common and doesn't hurt the plant. Not sure if neem oil will prevent rust from coming back. You can remove the leaves with rust, especially your plant is going dormant now. Make sure your indoor plumeria is not sitting on a wet soggy media to prevent root rot.

In spring you can remove the top soil (just in case there are rust spores) and hopefully you will have less rusts next year.

Tha k you very much!

Your leaves are falling off because it's time for plumeria to go dormant now

I thought so but it just started to bloom indoirs about a week ago and there are still many buds. Should I stop watering it?