Just cut back three of my trailing gardenias to the ground-- which have been in front yard for 7 years. Never had any problems with them. a few weeks ago, I noticed browning on the leaves. I sprayed them with soap water, thinking maybe whiteflies, although I did not see a profusion of them after shaking the plants. Today, these were totally brown and looked like they were dying. The others which are directly behind them seem to be in different stages of dying-- brown leaves, etc.
Whiteflies?? I more or less ignored them through the winter, which is what I usually do-- what now-- should I cut the rest back to the ground and hope for the best or try some other insecticide. I hate to lose them all--there are 10 planted together.