I have four, 12" square plastic planters on my back deck that I grow tomatoes in. I can see each year, the roots growing out of the bottom of the pot and the roots dangle in the water saucer I have below each pot. I figured my pot isn't big enough, so I got a deal on these used 30 gal heavy duty plastic barrels that had some sort of fabric stain proofing chemical in. I cut the tops of the barrels off so now that are about 26 " high. My question is: should I line these barrels with say maybe two 3 heavy duty 3 mil thick plastic trash bag liners so the chemical residue won't get into the soil? And also, since I won't have any water saucers to put underneath these barrels, should I drill some 1/2" holes around the bottom and cover with screen and fill the inside of each barrel with about 2" or 3" of gravel rock for drainage? Any other ideas or suggestions? I just am thinking my small 12" pots made my plants grow too tall and skinny since the roots didn't have enough soil..............am I wrong?