What happens when you plant a cat in a pot? It ripens! Ours went from light gray to deep black, and is now ready for picking from the cat bush.
As you can guess, what really happened is what always happens. Hilbert saw Hopper in the pot, and suddenly decided he wanted to be in the pot. So he wandered over, circled around, and eventually Hopper left for sunnier climes. Then the pot was all his.