Prying aside a corner of the gravel so you can access it with your finger or a moisture meter is the easiest way to go.
Some Costa Farms plants have a small layer of glued pebbles over the top of the soil. This creates a more finished, gift-ready look that a lot of our retailer partners prefer, but doesn't create a mess in shipping and in the store like loose gravel can.
While it looks nice, it can make watering a bit of a challenge. The easiest way to deal with this is to moisten some of the glue, then gently pry it off so you can feel soil-moisture levels with your finger or a moisture meter from your local garden center. For tips, check out our quick video or guide on caring for plants with glued pebble mulch.
If you don't want to mess with removing any of the gravel, you can drain off excess water if you accidentally overwater your planter by tipping it on its side over a sink so the excess water can pour out.