My last plant did the same thing. Mine was also in organic soil. I was feeding at a 7 ph and needed to be between 6 and 6.5 ph. Could never get a handle on it. I was feeding teas and was not giving the plant everything she needed. I switched up this grow. Using roots organic original and TPS nutes . So much better this time around! Crossing my fingers for flowering. 

If you get a handle on it , let me know what ya did. Still learning here.