First of all: she's so beautiful! :D
I'm having the same problem... My Mimosa is too small for her age... I believed it was because of the photoperiod (in Brazil we are going to winter and she's in vega) but it must be the pheno too.
I'm using organic soil too.
Keep up the good work and the harvest will come! Greetings from Brazil! Jah bless!
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