The flowers are all in the top 1/4 or 1/3 of the plant.
A patch of Dame's Rocket growing by a raliway.
This is an invasive non-native plant. It's not quite as bad as Garlic Mustard (Alliaria petiolata), but still bears watching. If you allow this plant to grow in your garden, keep a close watch on it.
I have seen areas completely taken over by Dame's Rocket.
Sometiems the petals are streaked.
The distinctive leaves.
This is what's left of the plant by October. These are the empty seed pods.