Your Plumeria has three basic needs: Water, Sunlight and Food. If you provide these, they will reward you with many lovely blooms.
Water is very important to your Plumeria. Your plant must have enough water in the summer months. Without adequate water your Plumeria will go into a suspended state or dormancy. The plant will abort flower stalks and the leaves will drop. Allow Plumerias to go dry in between watering, then a deep soaking is in order. Watering depends on the daytime temperature and humidity, a good balance is essential. Plumerias do not like standing water, do not use a catch bowl under a potted Plumeria.
When the plant drops its leaves in the cool fall and winter months, DO NOT WATER - only enough water is necessary to keep the soil slightly moist. If the temperature in your environment drops to 32º F, the plant may be bare rooted and stored in a freeze-protected area. The plant can be replanted in the spring and will do well.
6 to 8 hours of direct sunlight is needed for good blooming of your plumeria. Some varieties require some shade from the hot inland sun in the summer months.
To encourage blooming, Plumerias need a high phosphorus fertilizer. Refer to the AN. P. K.@ numbers on the bag. The AP@ is the Phosphorus content. Superbloom, Superphosphate and Hi-Bloom are some examples. You can use a 10-52-10 water soluble fertilizer at a rate of 1 to 2 teaspoons per gallon of water. A weaker solution and using it more often gives very good results if your plants are in pots. For plants in the ground, a 3-12-12 will work well. Apply at a rate of 1 pound per inch of trunk diameter, spread evenly to the drip line of the plant. Depending on your soil type 2 to 3 applications a year is sufficient.