Why do the busy Lizzies in our bathroom all turn brown at the ends of the leaves?

Amelia Powers, by email The usual cause of this is dryness in the air, although in a bathroom it may be that water droplets are collecting at the leaf tips because of the damp atmosphere and then the tips are being damaged as this moisture evaporates. This can happen with many soft-leaved plants in damp situations. Try to improve the ventilation if possible.