Posted: 16/07/2016 at 17:44
Ash is alkaline and coffee grounds are acidic so all I can think is that mixing the two have produced something the plant doesn't like (going back to my school science, that would be a salt.) Remove as much of the grounds and ash as you can and give it a really good watering to try and flush the stuff out. If it still looks the same in a couple of days, flush it with water again.
Tomato plants don't need any feeding until they have flowered and tiny fruit have set. You can then water it with a liquid tomato feed. I would avoid using ash on it which can be chemically too strong and coffee grounds don't really have any nutrient value, so avoid those too.