I have three plumeria cuttings that I planted last spring and one that I planted the previous year. They get full sun. I use Hawaiian Bud and Bloom 5-50-17 every two weeks in a soil drench. I use a moisture meter and water when it drops to 7-8 (roughly once a week). They had a bit of webbing near the trunk and I think I spotted a spider mite on one of them. I applied an organic insecticide soap. They keep getting small dead spots on the leaves (before and after the insecticide was applied). It's not rust, there is nothing on the underside. Some leaves are slightly mottled. They eventually turn yellow and fall off. Also, it doesn't appear to be sunburn, but more like chlorosis. I don't know what to do... Normally, I put them on the covered porch during rain. That last couple days we had a little rain and I left them out hoping it would help. It didn't. I live in coastal South Carolina Zone 8B. The climate has been very hot and humid lately and our rain is saltier than other areas. How do I help my plumeria? And how can I get the older one to bloom?

Plumeria naturally shed their bottom leaves from time to time. If you have treated for insects I would not stress too much about it.

Your plant will bloom when given sufficient space to grow(are your pots large enough?), appropriate fertilizer (I recommend a general times release fertilizer rather than what you are currently using) and plenty of sun. Sometimes it takes a year or two.....