I'm having exactly the same problem and it keeps filling up my notification wall if I leave it because there's one or two people just repeatedly trying to plant the same things which are failing to germinate underneath the weird dead ghost plants (see screenshot). It's very frustrating.
Just saw this in my save yesterday. Constant failed to germinate messages spamming my notifications and traced it to NPCs in the community garden, where my Sim had previously tried to remove dead plants and left a glitched out part of them behind. There’s new produce sitting in all the spots, and NPCs will just go around continually trying and failing to plant.
Or rather, one NPC in particular kept returning and doing this constantly. A few others would occasionally join him, but if you reset them they’d wander off and do something else. So I cheated to add him to family, built a little shed at the back of my lot, walked him into it and removed the door. Then I cheated to remove him from family again. Problem solved - the notification spam stopped. He’s still back there pacing, probably trying to get back to the garden.
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