I have a few brugs which started to have shiny curly leaves. I do not see any sign of a pest on the back or on the front of the leaves. Any idea why?
I'm not really sure- it could be broad mites, they are micro scopic and live between the tissues. I think a wiser person will chirp in and give you a better answer if there is one. If it is broadmites, Forbid gets rid of them.
A lot of times the leaves will curl due to environmental changes.. If that is the case the plant will fix itself and the new leaves will be fine.