Ask Mr. Smarty Plants

Bougainvillea is a plant native to Brazil which will not survive the winter outdoors in Idaho, but can be grown sucessfully indoors under the right conditions.

According to the University of Saskatchewan Extension service Bougainvilleas demand a minimum of 4 hours of direct sunlight and bright indirect light at other times. Without good light they will not flower and they may lose their leaves. They do well in normal room temperature. This can be lower in winter but never below 10C.

Water moderately during their period of active growth (spring through fall), allowing the upper 2.5 cm (i in.) of soil to dry out between waterings but never the entire root ball. If they become too dry they will shed their leaves. They will need less water in winter and should have good drainage at all times.

Pot in a loam-based media with added peat moss. They can be repotted each spring up to a maximum of a 20 cm (8 in.) pot, after which they should be top dressed annually with the same type of potting mixture.

Fertilize them every 2 weeks during their period of active growth with a complete soluble houseplant fertilizer with micronutrients (such as 20-20-20). Follow the label directions.

Personal experience tells me that the trick to success with this plant indoors is a bright location which is cooler than room temperature in the wintertime (50's and 60's) but not below freezing.