Technically it's soilless so I'd pH
I Agree It Is A Soiless Mix , It Is Vermiculite, Perlite and The Pro Mix Has Limestone In It I Think There Is One More Single Added Soiless Substance In The Pro Mix To Ph Balance The Pro Mix, I PH The Pro Mix Anyway To Desired Ph I Like When I Start Seedlings, I Also Sprout Seedlings !n Small Cups Of Pro Mix BX Also PH Balance For the Seeds In My Opinion The Most Critical Time Because They have To Sprout Or i Can Not Grow Her(s) I Useally Do Not Sleep Atleast Not Well When She And Or Shes Spout I Can Relax Some Also I Prefur Pro Mix BX I Useally Do Not Use The Other Pro Mixes, BUT If There Is No options, I Will Buy The Other Pro Mixes, Growing For Me Is My Therepy
