Only 2 plants in 6 x 6?

I would grow at least 4. If something goes bad with one or more of your plants, you'd only be left with 1 or none. Trust me, my first grow I lost nearly half of my crop due to powedery mildew. It is not uncommon for first time growers to make mistakes and end up with no harvest at all.

On the flip side of the coin, having only 2 plants allows you to really spend time with them and take care of them. That 1 on 1 time lessens the more plants you have, so tending to them every day can decrease the chances of losing them.

I'm just throwing food for thought out there to keep in mind....