Gardenia jasminoides 'Vetchii' in bloom on my backporch.

Frostproof gardenia variety.

Mystery gardenia variety.

• Description: An evergreen shrub with beautiful, glossy, dark green leaves. It can
  grow to a height of 3 feet. It produces fragrant creamy white flowers.
• Light: Bright, filtered sunlight or direct eastern sunlight
• Temperature: 60°F to 80°F ( 16°C to 27°C )
• Humidity: 50% to 60%
• Watering: Keep soil evenly moist, not wet. Never allow soil to dry out.
• Fertilizer: All purpose, balanced with chelated trace elements
• Soil Type: Acidic, well-drained, soil mix with added leaf mold or worm castings
• Pests: Whiteflies, aphids, and spider mites have been known to attack gardenias.
  Use physical controls for light infestations. If you choose to spray, always read the label
  before using any insecticide or miticide.
• Flowering: Cool temperatures ( 60's ) encourages flowering. Keep plant
  between 60°F - 75°F (16°C - 24°C) during the flowering period for longer lasting blooms.
• Propagation: Obtain five inch (13cm) tipshoot cuttings and place in a sterile
  rooting medium with bottom heat. Keep cuttings in a warm, humid atmosphere and they will
  root in four weeks.

Symptoms	Possible Causes	Remedies
Yellowing leaves	Alkaline soil or water, chlorosis due to trace element deficiency, underwatering, overwatering, insect pests	Use clean rainwater, distilled water, or add 2 tsp of vinegar/gallon of hard tap water, use acidic fertilizer with chelated trace elements, keep soil evenly moist, check for pests and eliminate
Flower buds fall off	Temperature too warm, acclimation, low light, low humidity, underwatering	Lower room temperature, move to brighter area, buy humidifier to increase humidity, keep soil thoroughly moist.
Leaves fall off	Environmental or transplant shock, insect pests	Avoid warm and cold drafts and sudden changes in environment.When transplanting gardenias, disturb roots as little as possible. Don't let delicate roots dry out. Keep a spray bottle handy with warm water. Check for pests and eliminate.
Malformed buds	Temperature too warm, insect attack	Lower room temperature, check for pests and eliminate
Bleached leaves	Light intensity too strong	Avoid hot afternoon sun, increase distance from high intensity lights.
Stunted growth	Cramped roots, environmental shock, insect pests	Check rootball, keep growing conditions as stable as possible, inspect plant for pests
Brown spots on leaves	Leaf spot disease, Anthracnose	Use neem oil