Down on my laurels
My cherry laurels have been suffering since the winter (one appears completely dead), and I'm hoping (with the exception of the dead one) that this is a problem the remaining laurels can rebound from. Is this a fungus or something more serious? Is the dead one beyond all hope? How quickly do I need to remove it so as not to leave the remaining ones vulnerable? Can I plant another in its place? These are north facing, and line a deck.
Montgomery County Maryland
There may be several reasons for decline and you will have to do some detective work. In general, cherry laurels grow best in a well drained soil in morning sun and afternoon shade. Has something changed in the area such as drainage, downspouts? They will not be happy in a poorly drained soil and susceptible to roots rots. Check the drainage in the area.
Make sure the shrubs are not planted too deeply as they can be susceptible to boring insects. These insects are also attracted to thick mulch. Keep mulch no thicker than two inches and away from the base of the stems. Look around the base of the stems for holes and frass.
Cherry laurels are also prone to scale insects such as the white prunicola scale. This is a sucking insect that can cause dieback. Monitor for these scale insects - look along the branches and stems for small disc or oystershell shapes that can be scraped off. See our website http://extension.umd.edu/learn/armored-and-soft-scales-trees-and-shrubs Once you identify the reason for dieback it is okay to plant another. Be sure to water during dry periods and keep mulch no thicker than several inches and keep away from the base of the shrub. Make sure the shrubs are not stressed as this makes them susceptible to insect and disease issues.
You also have the option of planting another type of shrub in the area.