I recently moved to a new house that has a beautiful laurel hedge, lush and green and around 15 feet tall. But right in the middle the bushes it's quite stunted. The leaves are yellow and the smallest of the plants is only around three feet tall with very small leaves. Is there something I can do to help these poor plants? It is the privacy hedge between us and our neighbors. They say it has always grown this way.
Have the soil where those plants grow tested. If I had to bet, I would bet that a neighborhood pet either does or did their business there and the excess nitrogen in the soil is burning the plant roots, causing the poor growth. Regardless of the cause, there is something in the soil that is hurting the plants and you will need a soil test to find out what. You should be able to get a free or very inexpensive soil test done from your local extension service.
Is it possible to graft new branches onto Laurel bushes? We have bushes which have been damaged and they have large areas which are bare or branches.
I am not sure how well they will take, but it would not hurt the tree to try. This article will help you with that:
https://www.gardeningknowhow.com/ornamental/trees/tgen/grafting-trees-what-is-tree-grafting.htm
How do I remove laurel tree sap off of a concrete drive?
This article will help:
https://www.gardeningknowhow.com/ornamental/trees/tgen/how-to-remove-tree-sap.htm
My established laurel hedge is showing a white powderish substance only on the new growth and causing the leaves to curl and go discolored. I have managed to prune the majority and have left the healthy ones.
It sounds like powdery mildew. These articles will help you:
https://www.gardeningknowhow.com/problems/get-the-cure-for-powdery-mildew.htm
https://www.gardeningknowhow.com/plant-problems/disease/powdery-mildew-homemade-and-organic-remedies.htm
Generally, cuttings would be the easier way to go with these plants; however, for the laurel, harvest the seeds before they have fully harden, but wait until the pods start to brown and open one. If the seeds are reddish in color, they should be ready to plant right then.
As for the pieris (lily-of-the-vally shrub, I am presuming), collect seeds right after their spring blooming and allow them to dry or plant them right away.
I have planted 200 three-foot high laurels. The leaves of most of them have turned brown on the upper part of the plant moving downwards. They are in an exposed area and I have been told are wind burnt. However, I have been advised to cut them back to below the browned part, otherwise the complete plant will die! Do you agree or will the leaves come back again in the warmer weather?
Yes, you can cut them back but I would not cut them back by more than a third of their growth as cutting them too much could do more harm than good.
Is there a laurel tree or shrub that has green leaves (2-4" long and 1 1/2 " wide) with a serrated edge? We live in Salem, Oregon.
A Japanese Laurel does have leaves like you describe. Here is more information on them:
http://www.backyardgardener.com/plantname/pda_a90f.html