Question: Why won’t my bougainvilleas bloom? They were in flower when I bought them, and they haven’t bloomed again since.

Answer: There can be several contributing factors. First, bougainvilleas need full sun. They also seem to bloom better if they’re somewhat rootbound. You’ll also notice that they have cycles of flowers, blooming heavily for a few weeks, then growing vegetatively for a period before they bloom again. They seem to flower best when they’re coming out of a dormant period, for example, in early spring or after the summer’s hottest weather. Keep them moist, and fertilize them sparingly with a complete-and-balanced, water-soluble plant food.