Gardenia Love by ClaraDon
TheGardenLady received this question from Mable.
I was told to dilute vinegar in water and use that on gardenia’s with yellowing leaves. Do you agree?
Gardenias by Jim-AR
Gardenias love acidic soil. If they are indoors, gardenias should be planted in an acidic soil that has a pH level of 4.5 to 5.5. If growing outdoors, have the soil tested before planting the gardenia to see that it has the right pH. See here.
Gardenias can have a host of problems. They are difficult plants to raise, especially when indoors. They suffer from a number of problems, yellow leaves just being one of the problems. Of three common things that can cause yellowing leaves is improper watering, too low light and the plants needing acid fertilizer.
Overwatering can cause the leaves to yellow.
The gardenia plant should be fertilized monthly between April and November with an acid fertilizer especially if you are using well or tap water. Some people recommend using distilled water because it is not alkaline. See here.
It is fine to use diluted vinegar on your gardenias. The Vinegar Institute recommends using diluted vinegar on gardenias (also azaleas and rhododendrons) in hard water areas at a rate of 1 cup of vinegar to a gallon of tap water (see here). The vinegar will help to release iron in the soil.
On Garden web, a reader has suggested another solution to get iron into your plant that she says has been proven successful for her plant.