Of course, everyone knows this one, the dandelion (Taraxicum official). Much loved by children for their sunny, yellow flowers and big, puffy, seed heads, these plants present a problem for gardeners who let their populations get out of control. However, a soil knife or dandelion weeder will easily pop them out. All you need is time and patience. If you have a particularly large crop, you might consider exploring this plant's various culinary and medicinal properties. Dandelion greens have long been used as a spring tonic. And the flowers are used to make wine.