Cole crop of some sort.

It's gone to seed; you'll find seedpods at the top of the plant.

Cussonia paniculata

Here is a link that might be useful: Cussonia paniculata

siliques would rule that out no?

This post was edited by saltcedar on Sun, Oct 13, 13 at 14:31

hmmm never occurred to me. With a mottled stem?

Might be a wayward ornamental kale or cabbage.

Here is a link that might be useful: {{gwi:352457}}

This post was edited by saltcedar on Sun, Oct 13, 13 at 14:48

Looks like a Brassica to me too. It has seed pods on it. The marks on the stem are the typical leaf scars of Brassicas.

Tree cabbage for comparison.

Here is a link that might be useful: {{gwi:352458}}