Most bougainvillea are in full bloom right now. Unfortunately, some are not. I received another bougainvillea question this week. Pilar writes that her bougainvillea is “…full of green leaves, but does not bloom, we miracle grow every two weeks, and water everyday”.
My advice is to back off on both the water and the frequent fertilizing!! Bougainvillea prefer to dry out between waterings.
About the Water:
Bougainvillea require good drainage; and they prefer to dry out in between waterings. In fact, the method nurseries use to force blooms is to withhold water. Because of their need for good drainage, be sure not to plant them too deeply.
The withholding of water forces the production of colorful bracts which surround the white flowers, as seen in the top photo. Each bract has three tiny white flowers as shown in both photos above.
Regarding the Fertilizer:
You’ve seen the 3 numbers on fertilizers? For lots of flowers and/or fruit, you need a fertilizer with a higher middle number. Those numbers, in order, are nitrogen (N), phosphorus (P), and potassium (K). The website for Miracle Grow that Pilar was using, shows that its chemical analysis is 28-8-16. The huge amount of nitrogen (28%) being applied to her plant is the reason she has such lovely leaves at the expense of flowers. The makers of Miracle Grow do produce a variety of types of fertilizer targeting the needs of different plants. Be sure to read the labels of whatever fertilizer you choose.
I promised Pilar I would write a blog post on this topic with greater detail. Watch for it to come out very soon.