If that's 1.2 sq. ft, then no...it's not enough room. If it's 1.2 sq meters, then yes...it's enough. Plants needelbow room, air circulation and access to the light.

Leaves that rub back-n-forth against each other will cause what I call leaftip irritation. It's like using an eraser on a cheap piece of paper. Sooner or later it rub's through the other leaf. (dead spots) Not really a big deal, but not something to strive for either.

Depending on where you got your seeds, now-a-days breeders seem to be worying less about strain integrity than the all-mighty dollar. As a result, the plants are not "stabilized". This means you, as the consumer, will usually get a couple of different phenotypes. One phenotype will take after the mom, one phenotype will take after the dad, and a bunch of phenotypes will be varying combinations of both. Some quality breeding houses are more careful, and they do back-cross to stabilize the strain they're selling. (hopefully only one or two phenotypes) This is a Readers Digest version, but close enough to explain the differences in growth, size, shape, colors, flowering times and effects.
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The little one might just be a stunted runt, struggling to keep-up. :jointsmile: