Light and position :
Provide good light , with some direct sun during the winter months . during the summer gardenias will do well in the dappled shade provided by other taller plants
Pay great attention to the detail of temperature where these fickle plants concerned. When buds are forming . ensure a steady day and night temperature of 16 C (61F) Swings in either direction are likely to cause bud drop. The temperature can rise by 5C (10F) when buds are not forming.
Always use soft, tepid water for gardenias . water moderately for the majority of the year , giving enough to ensure that the compost is thoroughly moisted . but allowing the top 12mm (1/2 in ) to dry out between waterings.from October to February provide less water , allowing the top 2.5-5 cm (1-2 in ) to dry out before watering again.
Humidity is a high priority with gardenias provide too little and the buds will drop . so mist daily with soft , tepid rainwater , taking care to avoid any open flowers as this will mark them .
Provide liquid feed in standard doses once every two weeks from march to September
Gardenias are lime haters, so when repotting , once every two or three years , use a special compost