common Laurel plants
 

I have several laurel plants a couple of months since planted. they are now about 12-15 inches high. They are being eaten by caterpillars (i think) as I've found the odd caterpillar on them. the leaves are being eaten from the edge, and circular holes are in the centre of each leaf. Any advice on how to get rid of/kill the caterpillars or what can I treat the plants with?

Thanks