Some days ago I posted some doubts about my Vinca (probably a Catharansus rosea) because it started to look bad. After taking care of it as told, it kept getting worse. The same thing happened with another potted flower plant I have. I asked for help at the local greenhouse, and kept the instructions, but it's not getting better.
These were my flowers before:
And these are the poor things now:
I don't overwater them. I spray water in the leaves sometimes (it's a dry summer) but not on the petals, and I take the water from the plates away so the roots don't rot. I keep them in direct sun light for about half an hour a day, and a lot longer in indirect sun light.
The temperature here has been over 34º C (93º Fahrenheit) and not very humid in general, and it's getting a bit colder right now, but not too much, 30-31º C (87º F).
I'm very concerned and don't know what to do. The rest of my plants are ok, and they don't have flowers. Could it be the bad ones are more sensitive?