If flowers are permanently in the room and are never allowed outside, and therefore do not get any rain, you should shower the plants from time to time. Not because they would miss the rain or because being watered is not enough for them. The reason is different: Like everything that stands around in rooms, dust also settles on plants.
Cleaning plants properly
Plants that have very large leaves should therefore be wiped down with a damp cloth every few months. Not only because it just doesn't look nice when plants are covered with a film of dust, but because the dust can hinder photosynthesis. On the other hand, when dealing with plants that have smaller leaves, dusting per leaf is not feasible. These plants are simply taken and placed under the shower together with the pot. You have to set the jet gently and the water should be lukewarm. Too cold or too hot water would be very harmful. Anyone who gives their plants a shower every few months will always be happy with them.