These cousins also share another common name: dayflower. Both are beloved by bees and other pollinators; both are invasive. One of the plants called widow’s tears is found in the genus Commelina. Its showy flower is made up of two larger symmetrical petals above (usually blue—some people think they look like mouse ears) and a tiny white petal below. Around the world, Commelina is used as food, medicine, dyes, animal fodder, and in the production of paper. The other widow’s tears (also called spiderwort) belongs to the genus Tradescantia, a New World native named for the sixteenth-century English naturalist John Tradescant. The blossoms range from pale pink and lavender to purple, and usually have three symmetrical petals. Spiderworts have been used for both food and medicine. Widow’s tears flower in the morning and fade by day’s end. When you squeeze the bract that surrounds the flower stalk of a Commelina blossom, a drop of tear-like mucilaginous sap oozes out. Tradescantia flowers wilt into a fluid jelly.
