Valeriana officinalis
Valerian has been used to ease insomnia, anxiety, and nervous restlessness since the second century A.D. It became popular in Europe in the 17th century. It has also been suggested to treat stomach cramps. Some research -- though not all -- suggests that valerian may help people with insomnia.
Valerian is a popular alternative to prescription medications for sleep problems because it is considered to be both safe and gentle. Some studies show that it helps people fall asleep faster and feel that they have a better quality of sleep.