Lavender

From the experts:

Lavender lags far behind sweet-smelling purple-hued sister names Violet and Lilac, but is starting to get some enthusiastic attention from cutting-edge namers. It does have a history as a name, going back to the eighteenth century, when it was also used for boys. But its recent attention comes from Lavender Brown, a witch character in the Harry Potter saga--though Lavender had also been previously featured as a best friend character in Roald Dahl's Matilda.