A gardenia is an evergreen acid loving plant. If you plan to keep it indoors, then be prepared to give it afternoon partial sun. It likes the fertilizer for azalias and rhododendrons, and doesn't like wet feet. The occasional yellow leaf is normal, in fact, the plant may have up to 10% yellow leaves during flowering. Do not be alarmed as this is normal behavior for the gardenia. If you live in a moderate climate, you can grow this plant outdoors. It loves a shade garden, and will happily blend in with azalias. My gardenia bush is about 18 years old, and is 8 feet tall and 15 feet around. I live in zone 9.