You can use Isopropyl Alcohol diluted at 50 % if using the 99%type. Use a cotton swab or fine brush. Although this just removes them and is not a cure.

Rick

I haven't posted on this forum for a long time but did have experience with scale on an Adenium that was gifted to me. The previous owner couldn't get rid of the scale so she gave it to me instead (I told her I'd try to save it). I did use rubbing alcohol with a cotton swab to remove any visible scales. But as Rick said, it is not a cure. More soon emerged and I went the insecticide route. I use Bayer's Advanced 3-in-1 Insect, Disease, and Mite Control. You can use the ready-spray version or buy the concentrate and dilute it yourself. I sprayed it 3 times, 10 days apart. Make sure to coat the top and bottom layer of the leaves plus the trunk. The scales had never come back and it has been 3 years.

Good luck to you!

Thank you so much! I will try the Bayer 3:1. Would that be safe on Plumeria also? I also have scale on my plumeria plants.

Yes, it's safe to use on Plumeria. I use the Buyer's 3 in 1 twice a year as preventative on all my plants, including my orchids that summer outside. I've a lot of plants and cannot afford to have an infestation of anything.