I managed to replicate this bug in my own world by first tinting the decoration, then flipping it around. Just flipping the decoration won't cause the bug, and neither will just tinting the decoration. I also found that it happens regardless which side of the screen the decoration hits - if it hits the left side, it'll scroll with that side of the screen, and vice-versa.
I'm running the standalone DS on a Windows 7 64-bit OS. I initially tested this in the Biodome, but it's not metaroom specific - I tested it in the Meso shortly afterwards, and the same thing happened.
Edit: After some more testing, I can confirm that this is not
an issue with the Garden Box - it's an issue with the game itself. Applying both the "tint" command and the "mira" command to an object will make its sprite behave this way as well, regardless of what it is (for example, Trix's Vampyre Castle toy).
Edit2: For further confirmation that this has nothing to do with the Garden Box...here's a picture of the bug in Creatures 3 standalone.