The narrowleaf or blue lupin (Lupinus angustifolia) is recognised by its dark blue, pea flowers arranged in dense spikes. The flowers develop rapidly into hairy green pods. It is often found growing on ground that has been recently disturbed, like other members of the pea family, the roots have nodules which fix nitrogen, making it tolerant of poor soils. Named after the wolf as it was thought to ravenously deprive the ground of nutrients but, in fact, it does the opposite.

Growing wild in Eurasia and North Africa, its cultivars have been adapted as a garden flower throughout the world. It is also grown as a fodder crop for animals and as the seeds are protein rich, the plants have potential for future development as a source for human nutrition.