I may have spoken too soon.

It worked fine yesterday, filling the pots, and refilling them as needed. When I stopped playing I turned the utility off, then shut down the game after selling my last plant. Then I quit the Constant Gardener.

This evening I've just opened the game and all the pots are empty. I started the utility and although the On button turned green, nothing happened. I tried shutting it down again, having it search for the pots again, then starting it, but still no change.