Check out the link below for Alternantera ficoidea , commonly called Joseph's Coat.

Here is a link that might be useful: {{gwi:366877}}

Looks like a plant I ordered last year (and carried over winter inside) from Singing Springs Nursery labeled Alternanthera dentata 'Rubiginosa' which will grow to 36" tall.

Eden's photo does look similar, but the A. ficoidea I have ('Red Threads' and a chartreuse form) grow shorter - to about 6 inches - although they will spread very wide. There may be other A. ficoidea selections ... mine have very tiny thin leaves, unlike those in photo.

Regardless, these are super plants, as easy as Coleus to grow. josh