Corn is good, mine will be hid in 1600 acres of corn. Probably more concerned about my weed than I am the corn crop!!!!! Anyway a tall plant that will really form a wall is castor beans. Be careful if you have a dog around though, because the seeds are pousinous, and it does not take alot. A castor bean can get upto 10 to 12 feet tall. Be c areful with thinking that will hide them, because people are fricken nosey. Last year lost all my plants because my mother and father-in-law got nosey. Have a plan ready if something happens. I got to spend 40 days in rehab on that one. Suck Suck Suck. Good Luck