Hi, 

Are you providing additional irrigation this summer? It has been dry and Montgomery county is headed into a severe drought area. 

Do you know if they were in burlap or container grown when planted? Was the burlap removed or the roots loosened from the container? Sometimes there is an internal girdling root that is impossible to see and it can cause some plants to struggle while others are seemingly fine. 

It could be that the plants closer to the maple aren't getting quite as much water since there could be some root competition from the maple near by. 

You could try to check around the base of the plants too to see if you notice any issues. You can refer to our Cherry laurel diagnostic page to keep an eye out on stressors and symptoms of other issues that could arise. 

Let us know if you have further questions. 

Emily

We wouldn't recommend adding any fertilizer now with the heat and you should really only need to add fertilizer to shrubs after doing a soil test which indicates a deficiency or the pH level being off for optimal growth. If you fertilize the adjacent lawn area or use organic mulch or leave fallen maple leaves in the bed over the winter, that would be plenty of natural fertilizer for the plants. 

You can find soil testing information here: https://extension.umd.edu/resource/soil-testing-and-soil-testing-labs/

Also just check for watering needs before supplementing. You can feel the soil under the mulch about 6 inches down to see if it is necessary then water deeply to soak the entire root zone letting it dry in between watering.