Bougainvillea is a tropical vine native to Brazil. The plant has spiny stems that have bracts--protective leaves--at the end that can be many colors, including red, orange and purple. The bracts protect the flowers, which are small and white. Bougainvillea can be used in hanging baskets or in flower pots or can be trained to grow like a tree. In the northern states, bougainvillea is grown as an annual, a plant that lasts for one year, and in the South it is used as a ground cover or hedge or on a trellis.
Bougainvillea are not fussy about the type of soil they are planted in as long as it is well-drained. Clay soil is one that holds water; it is made up of tiny particles, and the soil will feel sticky. Adding some organic compost or gravel to clay soil will help. Loam soil, which holds moisture the best, is a mixture of sand silt or clay and organic matter. When squeezed, it forms a ball that will crumble apart when poked. Sandy soils, which allow moisture to flow though quickly, feel coarse when they are wet or dry. The closer you can get the soil to being loamy, the better.
Bougainvilleas need their soil to be kept moist but cannot have their roots sit in water. To ensure this, do not use a saucer under the pot. The soil should not go dry between waterings. If it gets too dry, the plant will start to wilt. Bougainvilleas will soak up a lot of water during hot weather and will need to be watched closely.
Bougainvilleas do their best when they get full sun, at least 5 hours of sunshine a day. Any less, and you risk not getting blooms. They will not die if they are grown in shade or partial shade, but they will produce only leaves and few or no flowers at all. Bougainvilleas that are grown indoors all the time will, in all probability, not produce any flowers.
Frost can damage young plants; it won't kill them, but they will lose all of their leaves and bracts. The good news is that a bougainvillea will probably regenerate itself, as long as the frost is not prolonged. Bougainvilleas should be kept at a temperature between 70 and 85 degrees F during the day and 60 to 70 degrees F at night.
Bougainvillea use up the nutrients from the soil quickly, and they need to be replenished with the right type of fertilizer. Use a fertilizer that has a high percentage of phosphorus with micronutrients, iron and magnesium. Feed the plants a little bit at a time, but do it frequently. Fertilizers will list what plants they are best for; follow the manufacturer's directions to the letter.