Q. Why are my gardenia plant leaves turning yellow?
Gardenia, also known as cape jasmine, has leaves that sometimes turn yellow. This yellowing is iron chlorosis, the result of an iron deficiency. When soil pH levels are too high, iron in the soil becomes unavailable to the gardenia. To counteract this deficiency, add chelated iron to the soil to raise its acidity. You can also drench the leaves with the same solution.
Gardenias like full sun and warm conditions. Warm, dry conditions indoors can sometimes bring mites. Mist the foliage when humidity is low with distilled or rain water to reduce spider mite infestation.
Keep gardenias tight in their container. Use a clay pot and water as needed (use your finger to check moisture level). Let the soil dry before watering thoroughly all the way through. Allow to drain freely. Provide well-drained potting mixture on the acidic side (peat base); the pH should range from 4.5 - 6.2. Adding compost tea monthly helps to keep the soil acid.
For tips on a variety of gardening topics, see our Plant Information Guides.
- Courtesy of NYBG Plant Information Service