Gardenias are desirable for their large, creamy-white flowers that are not only highly attractive, but carry a pleasing fragrance. These evergreen shrubs are often grown indoors as potted houseplants because they require a warm, humid environment. For home gardeners who live in such a climate, gardenias can be grown outdoors. Although they are not the easiest shrubs to care for, according to information published by Clemson University Extension, their beauty and scent is well worth the effort.
Plant gardenias in areas that receive partial shade. A location that receives morning sun followed by afternoon shade is preferred. Dappled shade is also good, but do not plant these shrubs under a tree or anywhere where they will have to compete with the roots of other plants. Gardenias do not grow well if their roots are disturbed, according to Clemson Extension. For that reason, they do not transplant well.
Amend the soil with organic matter as deep and wide as possible. Gardenias thrive in well-draining soil that is rich in nutrients. Use leaf mold or compost, and make sure the planting site does not collect standing water.
Dig a hole large and wide enough to fit the root ball of the gardenia. Plant the shrub so that the crown of the root ball sits just above the level of the soil. Backfill the hole with the removed soil and water thoroughly.
Keep the soil moist, but not waterlogged. Cool, moist soil is vital for proper growth, according to University of Florida Extension. These plants are not drought-tolerant and should receive supplemental water during periods of drought. Consistency is key. Dramatic variations in soil-saturation will cause the buds to drop before opening. Spread a layer of mulch around the plant to help keep the soil moist.
Fertilize in early spring with an acidic fertilizer that also contains micro-nutrients. Iron is especially important. Fertilize again at the beginning of summer, but do not fertilize in the fall. The fertilizer should have a ratio of 15-5-15 (nitrogen-phosphorus-potassium), according University of Florida Extension. Follow the directions on the label for application for the size and age of your gardenia plant.
Prune your gardenia after it stops actively blooming. Remove wilted flowers and any leggy growth, as well as broken or dead branches.