Gardenias are semi-tropical, evergreen flowering shrubs that are indigenous to Japan, Taiwan and China. Growing a gardenia in your garden will provide you with beautiful, white, sweetly-fragrant flowers that will bloom from late spring through early summer. Gardenias can grow between 2 and 5 feet tall and are hardy in the USDA Zones 8 to 10.
Choose a location for planting the gardenia that will provide it light shade and filtered light. Make sure the area you choose for planting the gardenia is not near any concrete walkways or driveways, as this can cause a nutritional problem due to the alkalinity of the soil, according to the University of Florida.
Contact your local agricultural extension office to have a soil test performed to ensure the soil in the planting area can provide the proper pH. Gardenias are acid-loving plants--to flourish they require a soil pH of between 5.0 and 6.5. Consider planting the gardenia in a container if you suspect the soil in your garden is not conducive to growing a gardenia.
Till the soil in the planting area using a spade or a garden fork. Dig up the soil to a depth of between 10 and 14 inches. Remove all rocks, sticks and weeds. Amend the soil in the planting area by laying out a 2 to 3 inch layer of dehydrated compost, aged manure, leaf mold or other similar matter. Work the soil amendment thoroughly into the soil using the garden fork or shovel.
Dig a planting hole in the center of the tilled area that is twice the diameter of the container the gardenia is currently growing in, but no deeper.
Remove the gardenia from its current growing container. To do this, gently lay the container horizontally on the ground or on a potting bench. Hold the gardenia by the stem at the top of its root ball. Use a trowel, or a small hammer to tap down on the rim to loosen then slide the container from the root system.
Place the gardenia into the planting hole. The top of the root ball should be at the same level as the rest of the garden soil. Add more soil to the planting hole if needed until you are sure the gardenia is sitting at the proper level. Fill the planting hole half full of soil then pour water into the planting hole until it is full.
Scoop in garden soil until the planting hole is full of soil. Then create a dam of dirt in a saucer-shape that is approximately 2 to 3 inches high and about 16 to 18 inches in diameter. Fill the saucer up with water slowly so it can reach down to the roots. Spread a 2 to 3 inch layer of mulch around the gardenia. You can use grass clippings, leaf compost or other material.