Thoughts For a Typical Grow Room. These are some of the things to consider planning your grow room. If you go the soil mix route and you’re using around six, ( most states will allow personal grows in this neighborhood when it’s legal) 7 gal pots (you can go smaller if you need to), you’ll need about about 50 gallons of soil mix and about 25 pounds or so of amendments. You want to be in a convenient location with […]