I have 2 small Begonias that have broken out in white spots. The spots are only on the top surfaces of the leaves and do not appear to have developed on the stems or flowers. The plants are in pots attached to a lattice on the north facing wall of a west facing, upper level balcony. They get full westerly sun from 1pm-ish. The are only 200m from the ocean, so the air is always dry and salty. They are very well protected from the rain and the southerly winds I water the dirt in the morning only and try my hardest to not wet the leaves. They have been doing well and flowering constantly for the last few months - the white spots have not seemed to have had any impact on the amount of flowers they produce. What should I do about the white spots? p.s. I am new to gardening and I will really appreciate any good advice that I am given