Never a bad idea to slip a plant out of the pot and have a look at the root ball if you think it's in trouble. A lot of potting mix is made of mostly peat moss, which if it dries out is really hard to get wet again. So you can water regularly, and the water disappears into the pot, but it's just going around the solid dry brick of the root ball, not soaking in, if it dried up and solidified at some point.
That was a lot of words to say, when you do plant it in the ground, be sure to break up the ball of potting soil and make sure it's well moistened. Sometimes the plant will need to sit in a bucket of water to get re-hydrated.
