Eryngium agavifolium
Height x Spread: 150cm x 60cm
The large cone thistle flower heads of this plant are green and white in colour, and produce plenty of nectar for bees. The flower stalks are very tall with the spiny, exotic Agave-like foliage creating a large basal rosette.
Rather than being at the back, it is a plant that is better in the middle of a border as something you look through or around. Full sun and poor soils make by far the best conditions for this plant to thrive.