I’ve posted this before but just as a reminder… YOU can grow this, this is in a 10 gallon $3 fabric bag
Grow a couple on your deck… impress those damn nosy neighbors
Do it!
Personally, I think this is plant stress. Because ruderalis adapted in very low light conditions, the need for high PPFD lighting isn’t needed as much. So while it presents as calcium it’s not because it’s unavailable, it’s because it likely can’t uptake it fast enough. I’d try running 12:12 from here on out. Especially if it already topped out.