When you upgrade the garden, you should be notified that your plants will die in the upgrade. I know it doesn't make a lot of real world sense because it's not even touching the plants, but I didn't bother to spend the extra time to make content for an accessible garden plus an under construction greenhouse.
If you played Beta 3 of v0.18, that in-development build was buggy and cause this permanent bug to be present. You may need to restart your save.
Hey there, thanks for the reply! I must have overlooked the message about plants dying during the upgrade. No big deal either way. As for the build I'm playing on, it's the release version of v.18. I downloaded the game in its entirety after the official drop using the mirror link. Since resetting back to a pre-garden save, I've yet to encounter the problem again, though I've yet to attempt the upgrade again. When I get around to it, I'll make note if the error occurs again, along with a proper capture of the error message. Thank you for your time!
