I have a 4 foot plumeria and it has black tips on 2 of the 3 tips. It has only ever flowered once and does not get a large amount of leaves even before the black. It still has a healthy stem and the 3 branches are still solid other than the tips. Can I cut it down and start it all over, can i get it to bloom and leaf more? My tree is over 10 years old, started from a cutting.