The seedlings will stretch on you, its always a good idea to leave a few inches of space in the container to add more dirt after it sprouts. That goes for planting seeds as well as transplanting to bigger pots. Always leave room. It will need the support. People also get creative with pipe cleaners, popsicle sticks, string, etc.
you get out what you put in man.... Foxfarms soil is good, nutrients are meh. I would
never put anything Miracle gro in my garden, not even the
perlite.
@orville petry Cannabis can grow and produce smokable buds in a variety of conditions, its a very hearty plant. Just because you CAN doesnt mean you should... With better lighting and a better choice of nutrient rich soil you could have easily yielded twice as much.