Towards the end of the outdoor season last year, at the end of August, I germed bagseeds outdoors just as practice before I ordered by actual beans. I didn't take particular care like the attention I tried to give my first round indoor plants and just let them go rather. However, I did get a plant that turned purple, but then didn't stop getting darker until it turned completely black. Here's its neighbor plant's leaves next to its as a comparison, and a closer shot too.
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