Hedmonanswered grow question 6y ago Hi N.,
for me, there are several significant factors:
-The first that comes to mind is the flowering stage, the 12/12 light cycle, and the appearance of the first pistils. This can set you back by 1 to 2 weeks on your nutrient calculator, and this delay won't satisfy you in the 11th or 12th week for your harvest.
-The second is indeed the rhythm of the genetics you have. Often in the description found on the seller's page, you can see either a stable genetics, making the description accurate, or a genetics that can be influenced by the dominant traits of the parents. (this will affect flowering time, taste, size, etc...)
-Then the question? Are you using nutrients? This also influences the size of the fruits; there's no secret about that!
I hope to help you understand better!
Happy growing to you!