Please help me revive my poor shrubs!

Three years ago I over-trimmed some of the 10 shrubs along the side of my house. I'm pretty sure they are in the evergreen family. I think "box" was part of the name. They are currently approximately 2 feet tall and I have them trimmed round. Three of them have the looks of being 1/4 - 2/3 dead, but, one of them only has one small branch with some green on it. I've cut off some of the dead branches. i left some of the crunchy stuff there. I knew that it was going to take a few years, but it's been 3 years and nothing has changed. They get approximately 6-8 hours of full sun. I'm actually embarrassed about how they look!! The other parts of my property look nice and people always compliment me. What in the heck can I do to promote some green growth??

  2 answers