Only the new pseudobulbs will bloom and after they bloom they can’t bloom again. The rhizome on a cattleya is like a large creeping vine that sends up new pseudobulbs, one after another. For many cattleyas only the very last pseudobulb will bloom. On other cattleyas all the pseudobulbs produced that season can bloom.
On some plants all the new pseudobulbs will bloom together. On others they may bloom sequentially so the plant stays in bloom longer. Not all new pseudobulbs are guaranteed to bloom. Many often don’t. At the beginning of the next growing season the rhizome will start to grow and produce more new pseudobulbs and the cycle begins again.
Even though the old pseudobulbs can’t bloom they shouldn’t be removed if they’re healthy because they add to the over energy and storage capabilities of the plant. As the plant increases the number of old pseudobulbs each year, it can produce more and larger flowers.