The May lily, also sometimes called lily of the valley, is a type of forest lily native to Europe. Many botanists believe it may have originated in the ancient forests of Ireland. It has a long narrow stalk with dark green stems and leaves. The flowering part of the plant is white, with broad curved petals that surround a center shaped like a bell. Many ancient herbalists believed the May lily to have significant medicinal properties, though today it is widely consider to be a poisonous plant.
Even though it is likely native to Ireland, the May lily is now found all over Europe and North America. The flowers prefer dark shady woods, but with proper care, they can be grown in most home gardens. Most experts agree that the best time to plant the May lily is during late summer or early fall, preferably in early to mid-September.
May lilies are generally started as bulbs, and it is considered a good idea to plant the bulbs quite deep, as they will need to be able to survive winter temperatures. Holes should be dug at around 14 inches (35 cm) in depth, with spacing between plants at around 6 inches (15 cm) and 9 inches (23 cm) between each individual row. Some gardeners suggest digging the beds a few weeks prior to planting, then right before planting, turning the soil a few more times.
May lilies prefer shade or partial sun and moist well-drained soil. Areas of the garden that have standing water should probably be avoided, or top soil should be added until the water disappears. When planting the May lily, it is a good idea to fertilize immediately. Organic fertilizers such as manure or compost are recommended, but chemical fertilizers can also be used, as long as they have been developed specifically for lilies. Lilies of all types are prone to chemical burn, so caution should be used with any chemical fertilizer.
The May lily has a long history of medicinal use. Tinctures derived from the plant were once believed to benefit heart patients, as it appeared to act as a diuretic, much in the same way as the modern drug digitalis. This tincture was commonly given to soldiers on the battlefield as a protection against poisons. Today, most experts agree May lilies can be dangerous when used as a medicine or dietary supplement. The Food and Drug Administration of the United States has categorized May lilies as a poisonous plant that is unsafe for uncontrolled use.