SARAH BROWNING For the Lincoln Journal Star (This article is provided by All-America Selections, including pictures and plant information. Visit them at all-americaselections.org for additional information and pictures.) All-America Selections has announced six flower award winners this year, including two Gold Medal winners and four National winners. Gold Medal awards are reserved for breakthroughs in plant breeding, signaling a plant with a completely unique feature not previously found in similar plants. So Gold Medals are awarded very rarely. National awards are given to plants with consistently great performance across the United States. To see pictures of these and other great plants visit the All-America Selection website, www.all-americaselections.org. Begonia Viking Explorer Rose on…