The buds on two of my rose plants are being attacked by something that damages the outer petals. I've been spraying with an organic pesticide but it doesn't seem to be having much effect. What can effectively treat this?
my first thought before even seeing the picture that came to mind was possible thrips damage. But you have also said very hot and organic pesticides. I don't live in india but have found that hot summer days in Illinois we have to watch all types of pesticides organic or not especially if they are oil based in the heat. the trick is not to damage the plant more than the bug will. Do yourself a favor and treat in early cooler temps of the day or if lucky on cloudy days for less damage.
The temperatures are very high here in summer and the sun is very strong, so spraying in the morning is not advised. But I will try doing so when the monsoon comes and humidity is very high. Meanwhile, I saw some tiny black insects on one bud yesterday and sprayed immediately. I looked up thrips on the Net and it does look like that could be what is damaging the buds.