I think this is a great question and we get it all the time! It's a personal preference but I agree with the others, I count first cotyledon leaves as day 1 However, I have heard the occasional grower start their count at the day seeds are started.
I know you didn't ask about this but when it comes to clones it gets even more complicated! In that case I personally would count day 1 as the day you first see roots, but if you get a clone from someone else there's no way to know how old it is!
I know you didn't ask about this but when it comes to clones it gets even more complicated! In that case I personally would count day 1 as the day you first see roots, but if you get a clone from someone else there's no way to know how old it is!
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