Sometimes, as the season transitions from winter to spring, the lower, older leaves will naturally dry out. I used to worry about that, then I saw it is a normal occurrence. So be careful with watering at this time. It is just letting go of the winter leaves, and is actually going to make newer leaves from the middle of a cluster of leaves or up and down the stems or branches; or it could be gearing up for some new blooms. The plant is slowly redirecting its energy to the new growth.
