Best Tough-To-Kill PlantsFor those of you, like me, who have a tough time keeping plants alive raise your black thumbs! It's not just the flowers from your honey or the houseplant as a house warming gift -- pretty much anything that comes into my care ends up as compost a few days or weeks later. And I can't even think about starting a garden. But plant killers rejoice! We've got an expert who can change those black thumbs a pretty shade of green by picking the right plants. From flowers to perennials, University of Minnesota Extension Service Master Gardener Julie Weisenhorn helped me find the best of the "tough to kill" plants for outdoors.