I have miniature roses in pots which get sun for the first half of the day. They are in organic compost especially for roses in pots and the leaves have brown spots on them and the leaves and the flower buds are very dry, and the leaves and the flower buds drop off if I touch them, in face some of the spindle stems drop off if I touch them. Does anyone know what the problem is? and what can I do to put it right if possible. Thank you all.