Answer: Fertilizers made for azaleas are acidified and your plumeria doesn't need the extra acidity. When fertilizing Plumeria you should use a high Phosphate fertilizer (middle number), like Peters "Super Blossom Booster 10-50-10". If you use a fertilizer high in Nitrogen you will make a healthy but tall and leggy plumeria. Plumeria only branch when they bloom, therefore you must use a fertilizer that will promote the most blooms, which in turn makes the most branches. If you find a Plumeria full of branches, then you'll know it's been a good bloomer.
What brand should you use? I recommend PETERS "Super Blossom Booster" because it is loaded with micronutrients.
Best wishes with your plumeria!
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