Lemon balm - Melissa officinalis

A herbaceous perennial  and non native in the USA.  Although it is now naturalized.  

It grows to a maximum height of (3 ft 3 in). The leaves have a mild lemon scent. During summer, small white flowers  full of nectar appear. 

The leaves are used as a herb, in teas and also as a flavoring. The plant is used to attract bees for honey production. It is grown as an ornamental plant and for its oil (to use in perfume making).  It is known to repel mosquitos, gnats and cats.

https://en.wikipedia.org/wiki/Lemon_balm