It'll take plants around 12 hours to die after last being watered, are you coming back to them after 12 hours?
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i think the problem is that they can't be watered unless they're out of water, so they might be like, in the middle of the cycle when i turn off my computer, so i wouldn't be able to water them at that moment, so the last time it was watered was maybe a couple hours before that? im not really sure cuz im trying not to waste all my seeds by killing them :(