How can I get my cat to stop digging in my houseplants? He doesn't poop in there.?

[Petunia]

I thought keeping the plants well watered would be a deterrent, but it doesn't work.

[chicki]

But he may be peeing in there and that is why he is returning. I would try some small pieces of gravel or stone making it several inches thick and that should keep him away.

[Skalywag]

Try putting some mesh screen around the potted plants. Just from the stem to the pot - so that the cat can't get to the dirt. Once he finds that he can't physically touch the dirt he'll be discouraged.