My Serissa is diseased?
Hi, I got my Serissa a few weeks ago from Bonsaiboy and I started noticing that some of the leaves were getting little spots on them, at first I thought it was just insect damage, and treated it with a natural bug soap, now it seems like a large number of the leaves are coming down with something, usually it starts at the tip of the leaf but they start to turn blackish brown before falling off. I thought this might be a fungus so I started using Bonide liquid copper fungicide diluted to the recommended concentration, but it doesn't seem to be helping. I only water it when the soil seems dry, and I keep a tray of gravel with water underneath it to act as a humidity tray. The soil seems like a mix of potting soil, wood chips, grit, and small pebbles and I have slow release fertilizer on it. I've been clipping off the leaves as they start to turn colors in hope that it won't spread but it doesn't seem to help. Is this a normal fungus or is my tree blighted and doomed to its fate?