Lysimachia vulgaris (garden loosestrife, yellow loosestrife or garden yellow loosestrife) is a species of herbaceous perennial plants in the genus Lysimachia native to wetlands, damp meadows and forests of Eurasia.ysimachia vulgaris (garden loosestrife, yellow loosestrife or garden yellow loosestrife) is a species of herbaceous perennial plants in the genus Lysimachia native to wetlands, damp meadows and forests of Eurasia.