The frost that Cincinnati experienced the second week of April has caused some of the foliage on my macrophylla hydrangeas to turn brown or black. I see similar foliage damage to some new trees that I planted last year, as well as a mature sweet bay magnolia tree. Is this damage only temporary or should I be concerned?
Not a good answer, but only time will tell. Don’t do anything at this stage – good chance we’ll have more frosts. In 2-3 weeks, then we can evaluate and determine what needs to be done. Probably temporary foliar damages – most trees and shrubs have the ability to re-leaf. Some may need a little tip pruning, especially the hydrangeas. But just wait and see, then react with pruning if needed in a couple weeks.