Some autos will not utilize some containers full size. They have a limited veg stage so once it roots whether with enough space or not she will flower when it is time.
She will be fine... I grew them in 1 gallon grow bags with enough rooting.
There are a few guys on here growing great plants in smaller sizes ... It saves wasting medium that will not fully used.
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One way I grew larger autos in small containers were like this .......
This a HEMPY STYLE GROW ( Perlite / Vermiculite mix 3:1 ) in a KIDS SAND PAIL.
It was under CFL at the time when I was growing that way back some years ago.
It actually grew pretty well for what it was , but Hempy grows really roots out better than soil. You know EXACTLY when she is dry and feeding is idiot proof as you can never overwater it .
I moved on to QUANTUMS but growing with spirals were a bit fun once I got it dialed.
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