Help, is my laurel dying?

I planted the below laurel in troughs exactly 1 year ago. The troughs are 50cm deep and live on the end of my balcony which is in shade from 1pm onwards every day. The laurel were doing fine until a couple of months ago when they started to look as they do. Any idea what is wrong with them? Also, does anyone know what type of laurel they are? Many thanks.