I would like to suggest one more thing for you to maybe do

get some 6x6, and make a base, so the drasins can work better, if just lating on the ground, them hole will suck moisture up as well as drain water

thus making corn get moldy on you

you can notch the 6x6 timbers to hold the round/barrel better too!

but sounds like a good way to save a few bucks