I migrated some of my Gesneriaceae plants out of my home. They include episcias, Streptocarpuses, and a few African violets. All of these plants grow from stem cuttings and thus, taking more space in my house. I noticed that grasshoppers and some unidentified insects eat their leaves and they turn ugly in just a couple of days.
I usually make natural insecticides from some garlic juice combined with little soap if necessary. And this works like a charm to tomatoes some and other fragile plants outside. However, if this is done to a my Gesneriaceae family plants it works, but it causes permanent brown spots or areas on the leaves in just couple of hours. These kind of plants don't tolerate water on their leaves even if it's pure water .
Perhaps, anyone ever encounter a similar case and know how to handle it? Tricks? Better insecticides?