Gardenias require high humidity and a warm climate to thrive. Often a gardenia plant purchased in prime condition from a nursery begins a slow decline once at home. The buds of the temperamental flower will often fall off the plant before opening if conditions are just slightly less than perfect. Avoid the frustration of a flowerless plant with a bit of care and perseverance.
Keep the temperature between 70 and 74 degrees Fahrenheit if you have your gardenia indoors. Lower the temperature by 10 degrees at night.
Place gardenia plants in full sun inside and partial shade outdoors. Bring your gardenia inside if the temperature threatens to drop below 60 degrees Fahrenheit.
Line the bottom of a tray with small stones, and add water to just below the tops of the stones. Place your gardenia container on the tray to provide extra humidity. Make sure the bottom of the gardenia pot does not come in direct contact with the water.
Keep the soil of your gardenia plant moist but not soggy. Never let the soil dry out completely. The buds on the plant will drop in soil that is too wet or too dry, so try to find a happy medium.
Apply a fertilizer specially made for acid-loving plants each month from April to November. Always follow the instructions on the fertilizer package.
Check your gardenia for bugs regularly, especially if your plant has spent time outdoors. Remove any visible bugs and treat infestations based on the variety of insect.