Plant gardenias in a soil with lots of peat moss or composted bark mixed in about 6 inches deep. Fertilize them with a product for acid loving plants, such as Miracid, following label directions. Water with rainwater if you have it available to minimize the high pH water that is common in your area. Proper fertilizing and pH is important to minimizing or eliminating the yellowing leaves caused by iron deficiency. Brown or black stems and leaves is usually a sign of root death. Soggy soil conditions or dry soil can both cause root death.
Here is contact info for the Gardenia Society of America:
Box 879, Atwater, Calif. 95301
Thanks for the question. Please stop in again soon!
Q&A Library Searching Tips