Find a place with partial shade and avoid afternoon sun. When planting, I would keep it at the same level as it has been growing in the container. Be sure to add organic matter and provide good drainage. Yellow leaves and buds falling off are signs of poor drainage. When you water, water the dirt around the plant rather than the leaves. Gardenias grow best in acidic soil. When the pH is too high, the gardenia isn’t able to take in nutrients including magnesium and iron. Again, this can cause yellow leaves.
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