Humidity! Gardenias love the south with their humid nights and must have lots of moisture in the air to set buds. Grow near a sink, set the pot on a bed of pebbles and water and mist, mist, mist. Spider mites also love gardenias so wash you plant with mild soap and water often to keep any mite colonies from getting started. This is one plant that would love to take a shower with you or spend time watching you soak in a hot tub. Just don't let this potted plant sit in it's own drainage water as the fibrous roots have a tendency to rot if they get too wet. If this plant sounds a bit demanding it is - but what beautiful diva doesn't make demands?