JB -
It sounds like you may have more than one kind of insect pest on your Carmelia and Gardenia. Their presence may be an indication that the plants are under stress for other reasons - improper light or watering, for example. Both are difficult plants to manage indoors.
Using alcohol swabs and wipes is not only exceedingly tedious, it is also ineffective. The juvenile forms of scale, mealybugs, aphids and spider mites are virtually invisible to the naked eye and they tend to hide in crevices where you cannot see or reach them with swabs. Hence, a very through spraying - drenching, really - is essential to effectively eradicate these pests. I recommend a solution of 5 parts water, 1 part alcohol and a squirt of liquid soap. But the key is to drench all leaf and stem surfaces until they are dripping wet. Yes, it is a messy task, but if you are really thorough, one treatment may be all that is necessary.
