Flowering potted plants are widely sold at garden centers in spring to help decorate outdoor living spaces. Many of these plants are tender, tropical specimens that will not survive temperatures at or near freezing. They can live through the winter indoors, potted up and cared for much like an indoor potted plant.
Potted, tender tropical varieties of hibiscus (Hibiscus syriacus), or Rose-of-Sharon, are commonly sold for containers to decorate outdoor living spaces during the summer months. Although also available in hardy varieties, these hardier hibiscus are not normally sold as potted specimens. Tender varieties will not survive winter outdoors in areas where temperatures dip to freezing and below, but they will easily overwinter indoors in a sunny window. Position them in a south-facing window and water when the surface of the soil feels dry to the touch. If desired, they can be cut back to create or maintain a plant of a size that will fit into the allotted space. Increase watering frequency and amount when active growth resumes in early spring and begin feeding with water-soluble fertilizer at the same time.
Actually a tender tropical perennial in its native Africa, geraniums (Pelargonium spp.) are widely grown as annuals in the United States. They can be easily overwintered indoors in a sunny window, and will even bloom all winter if they receive sunlight all day. To bring indoors, cut the top of the plant back to about three to four sets of leaves and remove all flowers. Pot up in regular indoor potting soil and put the plants in a south-facing window. Water when the surface of the soil begins to dry out. Remove spent blossoms as soon as they begin to fade to keep your geranium producing flowers all winter. Bring outdoors in spring after all danger of frost has past.
A flowering tropical vine widely grown as an annual, bougainvillea (Bougainvillea spp.) is native to tropical South America. Its flowers can be red, magenta, pink or white. It is a fast-growing vine, often reaching a height of 12 feet in a single growing season. To overwinter bougainvillea indoors, cut it back to about 18 inches high when outdoor temperatures dip below 60 degrees F. Put it in a cool greenhouse or seldom-used room where temperatures are cooler than normal room temperature. The ideal range is between 50 and 65 degrees F. Water only as needed to keep the soil from drying out. When the days begin to lengthen in spring, move it to a warmer location in full sun, such as a south-facing window. When outdoor temperatures warm to the 70s and all danger of frost has past, move it outdoors to a shady position for a few days to acclimate it to the stronger outdoor light levels, then move into full sun.