Hmm, that's very strange, never heard of that glitch before. What kind of computer are you using?
In the meantime, best advice I can would be to try stashing your plants, and then taking them out of the inventory and putting them back down again. Also, try closing the game window and reopening it. Sorry for the inconvenience!
Huh, jeez. Again, sorry about that. My only other advice would be trying to delete your game and reinstalling, and also erasing your save file and starting again. You could also play in browser. I'll try and see if I can replicate it, but there's something weird happening on your laptop that doesn't happen on mine when I test.
