I have to tell you that Puffin Afatty is quite an experienced grower that (IMO) gets quite phenomenal results. I have started clones in 12/12 as soon as they have a decent root system--usually at least 2 weeks. And mine never got over 15-18". Although I am an experienced grower, I do not get results like Puffin. So...do not be discouraged if you cannot achieve what the more experienced growers are getting and make the journey to learning to grow a pleasant one. You will learn a little more with every grow.