I finally got around to testing this myself and I was able to reproduce the bug by simply using max pumpkin fertilizers.

The tricky thing about this bug is, if it's really being caused by the sitewide +1 pumpkin perk (which I believe is still in effect), I'm not sure if you want me to tell Cherche about it because the solution might be to turn off the perk! XD

If it's important to players that the fifth pumpkin stays, the other solution might be for us to simply draw the fifth pumpkin and put it in the code (I say "simply" but I honestly don't know how easy it is, haha). I can ask Cherche if that's doable, although it's still risky to bring it up because there's always the possibility that she may prefer the easier solution of turning it off.

Not to mention there's another visual pumpkin bug that's been going on, which is that the pumpkin stages no longer show up at all in the house view. I have no clue what might be causing that one lol.

Either way, visual bugs are arguably embarrassing for a petsite, so of course we want to fix them, and I'll ask what can be done without getting rid of the extra pumpkin. Thanks for reporting this!

(Also, please feel free to post your feedback/suggestions at any time!)