Portuguese Laurel health

I have planted a row of Portuguese Laurel (prunus Lusitania) along our fence line and Iam concerned about there health and whether they are being over or under watered. The trees look in a sorry state with yellowing, drooping and in some places curling leaves. Please see the attached pictures.
Does any one have any experience looking after these trees and how best to care for them. We obviously don’t want to loose them.