The fungus known as black tip occurs after the plumeria crowns have been exposed to frost or sometimes just cold winter morning dew. The healthier and larger the frangipani, the more resistant it will be to black tip damage. Some fungicides treat it better than others but it can be treated. If the black tip is severe, the tip will die and new shoots will grow from the sides of the branch, creating branches. When you see new shoots growing from the side of the plant, you should cut off the dead tip with a clean cut. Sometimes, rot can start in a damaged tip.
- In early spring,at the first signs of new growth, a bacterial problem commonly known as “black tip” can appear. This causes die back of the new growth but creates more branches.
- “Black tip” rarely kills the tree.
- The cause of the “black tip” fungus is low spring temperatures combined with high humidity. By late spring when temperatures increase the “black tip” disappears.
- To try and reduce its unsightly appearance seaweed extract liquid fertilizers can help. Begin foliar spraying at the first signs of new growth prior to the first signs of the “black tip” fungus and then spray once a week until early summer.
- Using hydrogen peroxide has been know to minimize the damage.
Black Tip Fungus is very hard to control once it gets a big head start. Black Tip can pop up at any time of the year. Black Tip Fungus loves cool, wet, and shady areas. When the conditions are right is can pop up virtually overnight, and spread like wildfire.
Black sooty mold forms a black mold on plumeria leaves. You’ll know if the black tip fungus has attacked your plumeria tree if you see black tips on the branches’ growing tips in spring. Affected branches will stop growing. If you catch this fungal disease soon after it first appears, you’ll have success in halting its spread. Spray the tree with an approved fungicide as soon as possible, and also cut affected branches back to disease-free wood.
If left uncontrolled it will kill the growth tips of mature trees, and kill entirely a small plumeria. If Black Tip has killed the growth tips on a mature plumeria and temperatures warm up, the black tip will die off. Then the blacked tips will callus and break off. Next, the plumeria will branch back out as if it was pruned. Sometime on a tree it’s not all bad, because it gets a ton of new branches, but if it happens every year, or disgustingly, twice a year you will have hell getting you plumerias to bloom.
You can help control it by controlling ants, which bring aphids and scale to your tree and feed on their sticky excretion. If you smear a think (1/2 inch) layer of a product called Tree Tanglefoot around the base of your plumeria tree, ants will be unable to pass over it. Black sooty mold can also result from exposure to whiteflies and thrips: control these pests with yellow sticky traps and insecticidal soap spray. If necessary, spray your tree with a broad spectrum fungicide.