Organic Cress: Land Cress (American). Barbarea verna.
This might have been the cress you grew in primary school in tubs. Grow it on for bigger leaves and tasty salads.
How to grow:
Sow seeds evenly into a well prepared seed bed, they do best in full sun. Or do them like you used to, reuse that pot the supermarket sold you, the seeds just need some kitchen paper and kept moist.
Keep slugs off when young. Easy to grow.
Favourite ways to eat them:
Sprinkle sprouts on salads or adult leaves in salads.
A close relative to the native Irish Barbarea vulgaris, which you’ll find it in disturbed places, biennial.
Avg contents: 1.5g (~450 seeds).