Sunflowers from last years garden. These are small varieties, eighteen to twenty four inches tall. The left one is a "Junior" and the one on the right is a "Big Smile". I have given up on hte large varieties. Anything over about six feet is too much work to get rid of at the end of the season! The twelve footers are like chopping down trees and removing the root ball can be a big chore too. Then it takes weeks to get rid of them in the weekly trash. If you cut the stalks to six or seven feet you can line the perimeter of the trash can and extend your volume of trash upwards! But, you then risk the the trash collector dumping the whole load in the street. Small is better!