looking good it really depends on the final size,,or the duration of flower,,I can fill a small area with many plants or just a few and take up same room,,I do a slow grow or try to lots of fimming and lst and super cropping,,I try to make 10-30 kola's ,,you said this is your first time scrog grow ,,the rule of thimb is if you put them in flower at 12 inches they will finish at 18-20 inches can be more depending on the strain,,and where it typcily finishes ,,or can be effected buy the size you have to grow in,,Is the Blie berrie a heavy sativa,,or a heavy indaca ,,or a Hybrid,, here is a break down for strain is pretty close,,
Here is the equation for indica strains. The vegged plant height (V) multiplied by 1.5 equals the plant height at harvest (H) or 1.5V = H If put in flower at 12 inches finish around 20 inches can be little more
Here is the equation for sativa strains. The vegged plant height (V) multiplied by 2.5 equals the plant height at harvest (H) or 2.5V = H. ,,put in flower at 1 foot can reach 3 foot buy finish or bigger
Here is the equation for hybrid strains. The vegged plant height (V) multiplied by 2 equals the plant height at harvest (H) or 2V = H. if put in flower at 1 foot will finish around 2 foot
here is a link they should help with any info
http://marijuanagrowershq.com/when-to-begin-flowering-indoor-cannabis-plants/