Valentine's Day is on the horizon, so you might want to brush up on your herbal love lore. For centuries, plants have been important to lovers, for a whole bouquet of reasons! Here are three you might not have thought of:

• Honeysuckle. The scent of honeysuckle was thought to induce erotic dreams; hence, many parents forbade their daughters to bring it into the house.

• Periwinkle. It was believed that people who ate periwinkle leaves together would fall in love. Another potion, less tasty: powdered periwinkle, houseleek, earthworms.

• Bay. If you want to dream of your future lover, pin five bay leaves to the four corners and the center of your pillow, before you go to bed tonight. Be sure to repeat the traditional charm (it won't work if you don't): St. Valentine, be kind to me, in dreams let me my true love see.