Every once in a while, there's going to be that moment when you look around your yard or garden, see a strange plant popping out of the soil and wonder to yourself just how it got there. Is it a perennial you didn't account for? Is it some volunteer laurel you need to uproot? Fortunately, Landscaper's Companion keeps track of more than 1,400 plants in 16 categories, including perennials, shrubs, annuals and houseplants. It'll let you know how much water and sun each needs, what temperatures they can survive and whether they're worth keeping. In case you're still second-guessing after all of that, there are nearly 6,000 photos to help you along.