How do you know what type of hydrangea you have? Hydrangeas are so confusing because there are several different ones.I break these down into two categories: prune a lot and barely touch. Prune a lot: panicles, like limelights and bobos; and arborescens (“smooth”), like Annabelles and incrediballs. Leave alone: macrophylla/“big leaf” or “mop head”hydrangea and oakleafs. They require little care. It’s really only the clearing out of the dead stems occasionally on the big leafs that is required. (