Coffee grounds can be beneficial to plants because they can help improve soil structure if they are worked into the soil.  Add a nitrogen fertilizer at the same time if you work coffee grounds into the soil.      
If placed on the surface of the soil, it should only be a thin layer and broken up because it can be easily compacted and will then repel water when it dries out.

You can also add some to your compost pile.

Here is some helpful  information from Oregon State Extension - https://extension.oregonstate.edu/gardening/techniques/coffee-grounds-composting