Not every room of the house has full sun, but those that do provide indoor gardeners with a unique opportunity to take advantage of the conditions provided. Many plants tolerate full sun, though some flowers need it to thrive. Take advantage of a sunny windowsill to grow bright, cheerful blooms in your indoor gardening pursuits.
The common garden geranium, Pelargonium hortorum, is a flowering plant native to South Africa. Grown indoors as well as out, these plants love full sun. Marked by dark-green foliage, geraniums require well-drained soil and tolerate dry conditions more than over watering. Pinching and pruning indoor geraniums keeps them from becoming leggy and thin. Geraniums thrive in temperatures around 65 degrees Fahrenheit during the day and are easily propagated from cuttings or seeds.
Nasturtiums, Tropaeolum majus Nasturtium, thrive in full sun and prefer sandy, well-drained soil. Growing up to 1 foot in height, these annuals are not tolerant of transplantation, and should be propagated in the pot they are to be grown in. Nasturtiums bloom in oranges, reds, pinks, yellows and white or a mixture of these colors. They require a high-phosphorous fertilizer to grow. In addition to their colorful flowers, nasturtium leaves are edible in salads.
Marigolds, from the genus Calendula, come in dwarf and full-sized varieties, ranging in height from 6 inches to 3 feet. Flowers are yellow, orange-gold, red or a mixture of these colors; they bloom best when the plant is given full sun and moist, well-drained soil. Marigolds bloom constantly throughout the season, and the removal of spent flower heads in a process called "deadheading" is recommended to keep the plants blooming, according to the Clemenson University Extension Office. Marigolds are propagated via seed or cutting.
Gardenias, known scientifically as Gardenia augusta, are characterized by fragrant white flowers. Grown outdoors as well as indoors, gardenias thrive in full sun but tolerate light shade as well. An increase in shade decreases the amount of flowers produced, according to the University of Florida Extension Office. These flowering plants thrive in acidic, well-drained soil and are propagated with cuttings or through grafting. Pruning should be done after the plant finishes blooming, but before the fall months; pruning too late in the season can reduce the amount and frequency of the next year's blooms.