You have a very serious, well-established scale insect infestation here. It is always much easier to treat pest problems when they are caught early. The immature scale insects are translucent and virtually invisible, so if you treat only the ones you see, you will miss the juveniles that will mature and come back to haunt you later.
Mix a solution of 5 parts water, 1 part isopropyl alcohol and a squirt of liquid dish soap. Thoroughly spray all leaf and stem surfaces until they are dripping wet. Pay particular attention to the lower stems where they emerge from the base. You must get complete coverage with the spray solution so you make direct contact with every scale insect. Rinse with plain water when you are done and remove the dead carcasses by wiping.
This is a messy task, but if done really thoroughly, you will only have to do it once.