I'm having an issue with several of my vfts. The plants are growing in a mixture of peat moss, perlite and sand. They get at least 8 hours of sunlight a day and are watered with distilled water, not too much water, just a bit in the bottom of the saucer and they never dry out. It's hard to tell from the picture but the traps turns black and then the new growth in the center of the plant turns black. Last year I had an issue with aphids and that was treated by immersing the entire plant in water for 48 hours. That worked great! This looks different and I don't see any aphids. Any idea of what it is and more importantly how to treat it?
This is a King Henry and it was doing great till the trap turned black. No new growth and the leaves in the center of the plant are tiny and black