Wait, what? Did the garden plot tell you that? Oh, yeah, didn't they lock plants to the plant-er for about 30 seconds after their ready? But still, that shouldn't be stopping you if you're the one who planted. Did someone else already replant?
Aye. Aye. And nay to the last question, because I accidentally used a guano on the seed I just planted. So yeah, 'twas funny to see the plot say that. :D