Speedwell

Myths, folklore, and symbolism
Speedwell (Veronica): In most varieties it is a blue-blossomed herb of the figwort family. The Latin name possibly derives from the Greek word berenike (bringer of victory); later the pun vera unica medicina was formed and thus symbologically related the plant to Christ as the "single, true medicine." Since speedwell supposedly drew lightning, people avoided bringing it indoors. (Herder)