Certified GKH Gardening Expert
This condition is typically caused by a lack of water. It is not uncommon to see it in the spring as the plant may not have received enough water over the winter and the dry winter winds further make the problem worse.
The leaves should regrow on their own now that watering will return to normal. Just as a precaution, I would treat the plant with a fungicide, just in case a fungus is to blame.
In the future, make sure to give it a good watering in the fall and consider mulching the base to help keep moisture around the roots. Also consider wrapping it in burlap to help keep the winds off it a bit.