Hey PuffinPine,
I see you're making progress. Plant is really green. Now I understand why so many peeps burn their plants by adding nutrients on top of FFOF.
I wanted to throw out an idea...not a perfect solution but it has merits. If you decide it would be better to wait till Sep. then you could use this time to do some training. Depending on how tall it gets...you could consider super-cropping. Maybe during flowering it may be cool enough to add another light too. Just a thought.
After this grow and to avoid this situation again, you could keep a clone momma inside. And then just grow when temperature allows it.
Also I think you should go swimming, go to an outdoor rock concert or some other summertime activity. Restore summer for enjoyment...like it should be.
JD