Question
i have an indoor patio rose. in the past month or so, it started getting what looks like small spider webs on mature leaves, although i don't see any spiders or other bugs. the tops of those leaves have what looks like brown dust on them. pretty soon, those leaves die and fall off. new leaves are still growing and looking great, but as they mature, this brown dust and web appears. do you know what is causing this and how it can be treated?

thanks!

Answer
What you are describing are very tiny spider like insects called Spider Mites. These insects suck underneath the leaves of their moisture and then the leaf area dies and you see what looks like dust. These insects HATE water and if you are organic you can try the following. Wrap the rose and the pot in a plastic bag tying it tight round the base of the rose stem. Then spray the whole plant with warm water at the kitchen sink. Make sure you get under the leaves wet. Do this once a week until there are no webs. However these insects are very hard to get rid of because they multiply quickly. Then I would use an insecticide such as Trounce or any other for household bugs. Just follow the directions on the label for spider mites.