We live at Broadkill Beach and have a Grandiflora magnolia that was planted 25 years ago. For the past 3 winters the leaves begin to turn brown on the edges and fall off. The first year it happened we thought it just got sand blasted from the huge dune they built up on the beach, but that hasn't been an issue in the past two winters. It has gotten all new leaves in the spring and still blossoms. Do you have any idea what is causing the recent change and what to do about it?
Magnolia grandiflora is a more southern species of magnolia. I think the browning is probably due to the uneven winters we have had that past few seasons. These trees can tolerate some cold, but prefer if it gets cold and stays cold. The fluctuating temperatures result in damage to the broad leaved evergreen species. Wind also plays a role, and maybe the dune they built has changed the wind patterns a bit and the tree may be exposed to more wind or wind from a different direction.
Hopefully it will recover and not be stressed year after year. There is not much you can do to lower stress on the tree. You can try to water during times of prolonged drought, but water deeply once a week if no rain, not more often.
Thank you for contacting Cooperative Extension,