i have two plants i put outside from my indoor garden because i over nuted them and they were unable to keep up with the other plants. i moved them outside and they have survived the worst and now they need a bigger area to grow in. they are probably only about 7 inches tall. Can i just grab a black trash bag and fill that with dirt and stick the plant in that? im looking for a fat pot that i can move around and i heard about the trash bag idea and that sounds like the cheapest and easiest way to go. help please anyone, thanks.