Thorns or flowers? Don explained that hard pruning of bougainvilleas is generally not recommended, because it makes the plants stop flowering and they then go into a strong, vegetative growth phase
Bougainvilleas in such a growth phase produce long, curved thorns in the leaf axils rather than flowers.
These thorns enable them to get a grip on tree branches and scramble up towards the light.
Encouraging flower How much your bougainvillea flowers depends on how it is treated.
These plants are very hardy and will survive without much water or fertiliser.
In fact, they thrive on neglect, and will put on a fabulous flower display for many months as long as they receive plenty of sunshine and are grown in a warm position. If you must prune to control the plant, prune lightly at the end of the flowering period.
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